卫辉一中2012届高三二轮备考抓分点透析之英语
情态动词和虚拟语气
【2012年高考命题预测】
作为历年高考必考语法点情态动词依旧会是2012年高考的热点。同学们首先应该着重掌握情态动词的基本用法，同时结合情态动词的用法学习虚拟语气。
【概述】情态动词也叫语气动词，有一定的词义，但本身不表示行为或状态，而只是表示说话人对所说动作的看法，认为它“可能”、“应当”、“必要”等。情态动词不能单独作谓语动词，只能和动词原形一起构成谓语动词。英语里的情态动词主要有：can(could), may(might), must, shall, will, would, need, dare, should, ought to。情态动词在任何主语后没有人称和数的变化。除must, need, ought to外，其他情态动词有表示过去时的形式变化：
现在式 过去式
can could
may might
shall should
will would
dare dared
【重难点突破】
一、情态动词
⒈ can 和could
⑴表示能力
can 表示现在或未来的能力，could作为can的过去式，表示过去的“能力”
Whales cannot live on land. 鲸不能生活在陆地上。
Before liberation few workers could support their families.
解放前几乎没有工人能养得起家。
* be able to 与can、could的异同：
◆be able to 可用于多种时态，can和could只用于现在时和过去时。
He will be able to go wi th us this afternoon.
他今天下午能和我们一起去。 （一般将来时）
I haven’t been able to see the difference yet.
我还不能看出区别在哪。（现在完成时）
He thought I would be able to do the work well.
他认为我能把这项工作做好。（过去将来时）
The sick man was soon able to stand up.
病人很快能站立起来。（一般过去时）
◆如果表示过去“能够”、“做到”，“设法干成了某事”，常用was/were able to …来表达（相当于managed to do sth.或succeeded in doing sth.）,而不用could。
We were able to get there before the meeting began.
会前我们终于赶到那里。
◆can间或可用于肯定句，表示理论上的可能性，表示笼统的时间，事物的特征
Anybody who wants to try can be successful.
只要想试，任何人都可能成功。
Scotland can be very warm in September. 九月份苏格兰会很暖和。
（2）、表示许可和请求
在日常生活中，can可以代替may,表示“允许”；could 可以代替can用来表示现在时间的动作，但语气较为婉转，表请求。
☆Can/Could I use your pen?
我可以用一下你的钢笔吗？（表请求）(could 比can更客气，语气更委婉)
Yes, you can.( 回答时不能说成could)
（3）、习惯短语：
cannot…too… 越…越好
cannot but 不得不
You cannot be too careful. 你越仔细越好。
I cannot but do so. 我不得不这样做。
（4）、can 和could 后面接动词的完成式，表示对过去情况的猜测或判断。can常用于疑问句和否定句，而could能用于肯定句，表示一个非事实的或不可能实现的可能性。
You were stupid to go skiing there. You could have broken your leg.
去那里滑雪你真是太傻了，你会摔断腿的。（实际上没有摔断腿）
⑸could have done本来能做而实际未做，表达遗憾的感情色彩
----I stayed at a hotel while in New York.
----Oh, did you? You could have stayed with Jane.
在纽约期间，我无处安身，只好住在旅馆里。
嗷，是吗？你本可以和珍妮住在一起。（表达遗憾的感情色彩）
⒉ may 和might
⑴表示“允许”或“请求对方的允许”，might 比may 语气更客气、更委婉
May/Might I take the book out of the room?
我可以把这本书拿出房间吗？（表请求允许）(might 比may更委婉，更客气)
⑵表示“可能性”
常用于肯定句和否定句，指说话人的猜测，认为某事或许可能发生。might并不表示某事过去可能发生，而是表示一种虚拟语气，指把握性不大，句中可以用may代替，不过may 要比might所表示的可能性要大。
He may/might come. You’d better stay here for a moment.
他或许来，你最好在这儿等他一会儿。
(I am not sure whether he’ll really come.)
I may/might not be back for dinner.
我可能不回来吃饭了。（I’m not sure whether I’ll be back.）
⑶用于祈使句，表“祝愿”
May you both be happy！ 祝你们俩幸福！
May you succeed！ 祝你成功！
⑷习惯搭配：may /might as well 还是…的好
You may as well give him the letter.你还是把信给他为好。
I might as well stay at home tonight. 我今晚还是呆在家里吧。
⑸在表示目的或让步的状语从句中构成谓语
Write to her at once so that she may know in time.
马上给她写信使她及时知道。
⒊ must
⑴表示“必须”、“一定”（现在和未来）
We must finish this before he comes.
我们必须在他回来之前做完这件事。
⑵must 和have to：
◆严格说来，这两个词是有区别的, must表示说话人主观认为的“必须”，而have/has to表示客观的需要，也可译为“不得不”
I really must stop smoking. 我真的该戒烟了。（我认为应该戒）
I have to stop smoking.
我得戒烟了。（可能医生的要求或身体的客观情况使我戒烟）
◆have to 有时态和人称的变化，而must没有
I had to write some letters last night.我昨晚不得不写些信。
I will have to meet Mr. Edward at three o’clock this afternoon.
我必须今天下午三点钟去会见爱德华先生。（将来时态）
◆must not=mustn’t 表示禁止，“不许”，“一定不能”
do not have to =don’t have to “不必”
You don’t have to go now. 你不必现在就走。
◆must 用于疑问句时，肯定回答用must, 否定回答用need not 或don’t have/need to
Must I hand in my paper now? 我必须现在交吗？
Yes, you must. (No, you needn’t. 或No, you don’t have to.)
⑶must用在反意疑问句中
在反意疑问句中，附加部分要和陈述部分的情态动词或主要动词在意思上相呼应，使用情况各有不同：当陈述部分中的must作“必须，一定要”讲时，附加部分用mustn’t 或needn’t; 当must表推测，作“一定是，准是”讲时，附加部分要根据must后的原形动词选用相对应的形式。
He must work hard at English, mustn’t he ?
他必须努力学习英语，是吧？
You must renew the book, needn’t you? 你必须续借这本书，对不对？
He must be a teacher, isn’t he ?他准是一名教师，是吗？（不说mustn’t）
You must have studied English for many years, haven’t you?
你想必学了多年英语，是吗？（不说mustn’t）
He must have arrived here yesterday, didn’t he?
他想必昨天就到了这里，是吗？（不说haven’t）
⑷must表示“偏偏”
The car must break down just when we were about to start off.
我们正要出发时偏偏车又坏了。
4、need 和dare
⑴need 作情态动词，表示“需要”，只用于否定句和疑问句中，无人称和数的变化。
We needn’t go there tomorrow. 我们不必明天去那里。
Need I tell you all the details? 我需要把一切详情告诉你吗？
⑵dare作情态动词，通常用在否定句和疑问句中，无人称和数的变化。
I dare not stand on the chair. 我不敢站在椅子上。
How dare you say such a thing? 你怎么敢说这种话？
⑶need 和dare 也可作行为动词，与一般动词的变化相同。
◆作行为动词（或实义动词）时，need后面接“to + 动词原形”。
Do I need to tell you all the details? 我需要把一切详情告诉你吗？
You didn’t need to come. 你当时没必要来。
◆dare在肯定句中（I dare say除外）和疑问句中，后面都接“to +动词原形”，在否定句中有时带to, 有时不带to, 如：
She dares to go out alone at night. 她晚上敢一人出去。
He did not dare (to ) do so. 他不敢这样做。
⑷惯用语：I dare say 表示“我想”、“大概”。
There’s something wrong with the radio, I dare say.
收音机恐怕有点毛病。
I dare say you are right. 我想你是对的。
⑸ needn’t + have +过去分词
表示过去本来不必做某事而实际上做了，“本不必做…”
You needn’t have come.你本不必来。 (=You didn’t have to come.) （事实上你来了）
He needn’t have waited for me.他本不必等我。（=He didn’t have to wait for me.） (事实上他等我了)
⒌will 和would
⑴表意愿、决心
在陈述句或在条件状语从句中，wil l 和would用于任何人称。
I will finish my lesson even if I have to stay up all night.
即使我整夜不睡觉我也一定要把功课做完。
If you will allow me, I’ll go with you.如果你愿意的话，我将跟你去。
⑵ would 可表示过去的习惯动作
He would sit there for hours sometimes, doing nothing at all.
他有时候长时间地坐在那里，什么事都不做。
Every morning I would go for a long walk.
我每天早晨都会走很长的一段距离。
⑶ 表示询问对方的意愿或向对方提出请求,此时，would比will 的语气更婉转
Will you please pass me the magazine? 请你把杂志递给我好吗？
Won’t you come over? 请到这边来好吗？
⑷ would 与like连用，表请求、提议，比will更婉转礼貌，这时would表示的是现在时间并非过去时
Would you like to leave your telephone number?
请留下你的电话号码好吗？
⑸ will 可以表示现在或当前的习惯性、经常性、倾向性。常译成“惯于”、“总是”
No matter what you say, he will always argue with you.
不管你说什么，他总是和你争论。
A wise man changes his mind, a fool never will.
聪明人能随机应变，傻瓜是不会的。
Water will boil at 100℃. 水在摄氏100度时总是要沸腾的。
⒍shall
⑴用于第一、第三人称疑问句，表示说话人征询对方意见或请求指示
Where shall I put my bag? 我把包放在哪里好呢？
Shall he come in or wait outside? 让他进来还是在外边等着？
⑵用于第二、第三人称，表示意愿、期望、允诺、命令、强制、警告、威胁等语气
You shall keep your room in order. 你须保持房间整洁。（表命令）
He shall be sorry for it one day, I tell you.
有一天他会后悔的，我告诉你。（表警告）
⒎should
⑴表示责任、义务、建议、劝告，用于各人称
You should study every day. 你们应该每天学习。（表责任）
You should always think of others before yourself.
你应当首先想到别人。（表劝告）
⑵表推测、可能，暗含很大的可能
I think he should be home now. 我想他现在应该在家。
You should know his address.你应该知道他的住址。
⑶should + have + 过去分词 表过去本应完成而未完成的动作
shouldn’t + have + 过去分词 表示过去发生了不应发生的动作
He should have arrived by this time.他本应这个时候到了。（其实未到）
⑷用在why , how开头的疑问句中或that 引导的从句中表达说话人感情色彩，表达意外和不满，“竟，竟会”
I’m sorry that you should think so badly of me.
你竟把我想得那么坏，我感到遗憾。
⑸用于if 引导的从句中，构成虚拟语气
If he should drop in, give him my message.
他如果来访，就把我的条交给他。
⑹用于建议、命令等的从句中，构成虚拟语气
We demanded that our wages should be raised. 我们要求提高工资。
⑺在It is necessary/ important/strange that…中：谓语动词常用should + do, 或只用动词原形，构成虚拟语气
It is necessary that he should be sent there at once.
派他马上去那是必要的。
⒏ ought to
⑴ ought to 和should差不多，都表“应当”，在很多情况下可通用，但也有细微的差别：在表示因责任、义务等该做的事情时，常用ought to ，在表示某件事宜于做时，多用should.
You are his father. You ought to take care of him.你是他父亲，应当管他。
⑵表推测，暗含很大的可能
If we start now, we ought to be able to get there in time.
如果我们现在动身，我们应当能准时到达。
⑶ ought to + have +过去分词 表过去本应做但实际上没做的事
oughtn’t to + have +过去分词 表示过去本不该做但实际上做了事
I ought to have written him a letter.我本应给他写封信。（实际上没写）
I oughtn’t to have written him a letter.我本不该给他写信。[来源:学_科_网]
★表示推测的情态动词用法归纳：
⒈ 肯定句中：
must (一定)，may (可能)，might/could (也许，或许) 其语气的肯定程度依次递减。其中，might 和could并非过去时态，只是语气较为委婉或可能性较小
⑴对当前行为、情况或状态的推测： must /may /might /could + do/be
He must/may/might/could be in the reading room.
★他肯定/可能/也许在阅览室里。
⑵对此时此刻正在进行的动作的推测：
must /may/ might/ could + be doing 想必/可能正在…
He must /may/ might/ could be watching TV at this time.
他此时一定/可能/或许在看电视。
⑶对过去发生的事情的推测：
must /may /might /could + have +过去分词 想必/可能已经…
You look very tired. You must have stayed up last night.
看上去你很疲劳，你昨晚一定熬夜了。
You may have read about it in the papers.
你可能在报上已读到这件事了。
⑷过去的一段时间内一直在进行的动作：
must/may /might/ could + have + been +doing 想必/可能一直在…
He may have been waiting for us for an hour. 他可能等我们一小时了。⒉ 否定句中：
can/could not 不可能，想必不会
may/might not 可能不
⑴对当前行为、情况或状态的推测：
can/could not +动词原形 不可能，想必不会
may/might not +动词原形 可能不
He may not be busy now. 也许他现在不忙。
He can’t be in the reading room. I saw him on the playground just now.
他不可能在阅览室里，我刚看到他在操场上。
⑵对此时此刻正在进行的动作的推测：
can/could not + be doing 不可能，想必不会在干某事
may/might not + be doing 可能没在干某事
They can’t be telling the truth. 他们不可能在说真话。
They may not be telling the truth. 他们可能没在说真话。
⑶对过去发生的事情的推测：
can/could not + have +过去分词 不可能，想必不会做过某事
may/might not + have +过去分词 可能没干过某事
He may not have achieved all his aims. But his effort is a good one.
他可能 没达到他的全部目的，但他还是认真做了努力的。
⑷过去的一段时间内一直在进行的动作：
can’t /couldn’t/may not have been doing
He can’t have been waiting for us so long.他不可能等我们那么长时间。
⒊疑问句中：
常用can/could来表示说话人的猜疑、怀疑或不肯定的语气
⑴对当前行为、情况或状态的推测：
can/could + 主语+ do/be
Where can he be now? 他现在会在哪里呢？
⑵对此 时此刻正在进行的动作的推测： can/could +主语+ be doing
It’s so late. Can Tom be reading? 这么晚了，汤姆还在看书吗？
⑶对过去发生的事情的推测： can/could +主语+have done
Can she have told a lie? 她会不会说谎了？
（2011?辽宁卷）21．If you __ go, at least wait until the storm is over．【C】
A．can B．may C．must D．will
（2011?江西卷）23．___ be the postman at the door, It’s only sis o’clock．【B】
A．mustn’t B．can’t C．won’t D．needn’t
（2011?四川卷）20．The police still have I found the lost child, but they’re doing about they ．【A】
A．can B．may C．must D．should
二、虚拟语气
1、虚拟语气的重点是：
1）．一些常见的虚拟语气的句型或结构。
2)．虚拟语气的特殊形式，即用来表示要求、建议、命令、提议、意愿等的主语从句、宾语从句、表语从句和同位语从句中的虚拟形式。
3)．主从句表示不同的时间概念、事实或假设情况，从而交错成为复合虚拟语气。
4)．含蓄条件句中的虚拟语气的表示愿望的虚拟形式。
2、虚拟语气的常见类型和句型
（1）由wish引起的表示愿望的虚拟语气
A．用wish表示对现在的愿望时，它所引起的宾语从句中谓语动词形式为：过去式（be动词用were）。
B．用wish表示对将来的愿望时，它所引起的宾语从句中谓语动词形式为：would, could, might+ 动词原形。
C．wish用于对过去的事实表示一种不可能实现的愿望时，宾语从句中的谓语动词形式为：had+动词过去分词或could, would + have +动词过去分词。
The picture exhibition bored me to death; I wish I had not gone to it.
（2）would (had) rather, would as soon, would sooner和would prefer所引起的从句中要求用过去式表示当时或将来的情况，用过去完成时表示过去的情况，表示希望或婉转的责备。
I’d rather you posted the letter right away.
我倒希望你把这封信立刻寄出去。
（3）由连接词in case, so that ,unless, lest ,for fear that引起的状语从句中，谓语动词要用虚拟形式，即should(might, would)+动词原形，
She put a blanket over the baby for fear that he should catch cold.
她在那个婴儿身上盖上了毯子以免他着凉。
The bad man was put in the soft-padded cell lest he injure himself.
(4) 虚拟语气在条件句中的应用
表示与现在事实相反：If + 从句主语 + 动词的过去式…，主语+should/ would/ could/ might + 动词原形…（be 一般用were）
表示与过去事实相反：If + 从句主语 + had + 过去分词…，主语+should/ would/ could/ might +have +过去分词…
表示与将来事实可能相反： If + 从句主语 + ①动词的过去式…，②should +动词原形…， ③were to +动词原形…， 主语 + should/ would/ could/ might + 动词原形…
If it had not been for his help(=but for his help),we would not have succeeded.
(5) 虚拟语气用于as if（though）引起的方式状语从句和表语从句中，其动词形式与wish宾语从句的形式相同。
She often laughs spontaneously, and her good humor breaks out as brightly as if it were a part of the sunshine above.
她常常发出发自内心的微笑，而且她那美好的情绪像天上一道明亮的阳光一样，常常流露出来。
They talked as if they had been friends for years.
他们交谈着，就好像他们是我年的老朋友一样。
(6)其它各种句型, as though, suppose, had rather, supposing, if only等等
If I were in a movie, then it would be about time that I buried my head in my hands for a cry.
二、特殊形式的虚拟语气
虚拟语气的特殊形式，即用来表示要求、建议、命令、提议、意愿等的主语从句、宾语从句、表语从句和同位语从句中的虚拟形式，其虚拟语气的构成往往是由should(可省略)+动词原形that从句。
A、 用于表示意愿、建议、命令、提议、请求等动词后的that宾语从句中，这类动词有：
ask要求 advise建议 arrange安排 beg请求 command命令 decide决定 demand要求 desire渴望
determine决定 insist坚持 intend打算 maintain坚持主张 move建议，动员 propose提议 object反对 order命令 prefer建议 require 需要 request要求 resolve下决心 recommend推荐 suggest建议 stipulate约定，规定 urge强调，促进 vote公认，提议 decree颁布（法令） pray请求
注意：这类动词后面除了可接that虚拟句以外，也可以接doing或者to do…来表达，一般情况下，意思没有什么差别。
She advised that we should keep the gate locked.（ 书面体）
She advised us to keep the gate locked.（口语）
She advised keeping the gate locked.(较随便)
B、用于It is+形容词或过去分词+主语从句中，这类形容词或分词有：
advisable合理的 decided决定的 crucial关键的 appropriate恰当的 determined决定的 commanded命令的 arranged安排的 essential紧要的，基本的 complied遵照 anxious焦急的 imperative迫切的 important重要的 desirable合意的 better较好的，更好 insistent坚持的 desired想要 asked请求 keen渴望的 incredible难以置信的 adamant坚定不移的 natural自然的 insisted坚持 necessary必要的 suggested建议 urgent紧迫的 ordered命令 shocked震惊的 vital极其重要的 possible可能的 strange 奇怪的 preferable （好一点） proposed提议 requested要求的 required要求的 recommended推荐 resolved决定的 probable（可能的） pity可惜，憾事 shame遗憾
注意：这类形容词后面除了可接that虚拟句以外，也可以for…to do… 来表达，一般情况下，意思没有什么差别。
It is essential that he should be prepared for this.
It is essential for him to be prepared for this.
C．用于由表示建议、要求、命令、请示等含义的名词引导的表语从句和同位语从句中，这类名词常见的有：
advice忠告 decision决定 demand要求 desire要求、愿望 insistence坚持 motion提议 necessity必要性 order命令 preference偏爱 proposal提议 pray恳求 recommendation推荐 request要求 requirement要求 resolution决心 suggestion劝告、忠告
This is their resolution that extra-curriculum activities be made part of their school life.
这是他们的决议：要使得课外活动成为他们学校生活的一部分。
The motion that the remark of the last speaker be expunged from the record.该提议要求把最后一个发言的人的从记录上除掉。
三、混合虚拟语气
有时主句和从句的谓语动词指不同的时间，这时需要用混合虚拟语气。一般来说，在这种情况下，主从句谓语动词指代的时间不同，所以我们又可以错综时间条件句，在这种虚拟情况，动词形式应根据实际情况灵活使用，在做这些题目时候尤其要注意每道题目的提示语：时间状语。绝大多数情况下，从句或者主句都有相关的时间状语，这是我解题的关键。
If you that late movie last night, you wouldn’t be so sleepy.
A. haven’t watched B. didn’t watch
C. hadn’t watched D. wouldn’t have watched 答案选C。
Many dead would now be alive if they have not attempted to return for something.
Had Paul received six more votes in the last election, he would be our chairman now.
混合虚拟语气还有一种情况就是事实和虚拟假设的混合句，这样的句子不仅仅是时间的不同，而重要是事实和假设的混合。
I would have gone to visit him in the hospital had it been at all possible, but I was fully occupied the whole of last week.
该句前半部分是假设虚拟，而后半部分是事实的陈述。
Your math instructor would have been happy to give you a mak e-up examination had you gone and explained that your parents were ill at the time.
该句前半句用的是假设虚拟，后半句主句也用的是假设虚拟（如果你去并且解释的话），但是后半句的从句用的是事实语气，因为“父母病了”是客观事实，故不需要用虚拟形式had been。
四、含蓄虚拟条件句
含蓄条件句是指句中没有明显的虚拟条件句，而是利用其他手段来暗示存在虚拟条件。但是这类隐含式虚拟条件句往往都可以转化为if引导的条件句。常来表示含蓄虚拟条件的手段有：
（1）介词或介词短语，如but for, but that, without, in case of, under more favorable condition等。
the leadership of the party, we could not be living a happy today.=If there hadn’t been the leadership of the party, we could not be living a happy today.
A. In spite of B. But for C. Because of D. As for 答案选B。
But that she was afraid, she would have said no.
(2)连词，如：so that, unless, in case, supposing, lest, provided(倘若……)，for fear that(唯恐)，in order that, on condition that, if only(要是……就好了)等。
She listened carefully in order that she might discover exactly what he wanted.=if she listened carefully ,she might discover exactly what he wanted.
If only I had more money, I could buy a car.
(注：lest, for fear that 和 in case 引起的从句中谓语动词多用should+动词原形，但可以不用虚拟语气，而用动词的陈述语气形式。)例如：
The foreign teacher spoke slowly in case we misunderstood him. 这位外籍教师说得很慢以免我们听不懂。
Care must be taken in using this method lest overflow should occur.在使用此法时要小心谨慎，以免会发生溢流现象。
（3）通过上下文及内在含义，句中往往有but, otherwise, unfortunately等类似转折词。
I thought the children when we returned home, but they were still awake.
A. were sleeping B. would be sleeping C. had been sleeping D. would sleep选择 B。
(4)形容词及其比较级
A more careful person would not have made so many mistakes.
A less conscientious man wouldn’t have tried so hard to get this job done.
(5)分词短语
Having known in time, we might have prevented the accident.
Born ten days earlier, the boy could have seen his late father.
(6)动词不定式短语。一般intended/meant/hoped/wished/planned 或 was/were+不定式完成式或had intended/meant/planned/hoped/wished/+不定式一般式表示虚拟。
I intended I should call on you, but I was busy at that time.
To hear him speak French, you would take him for an Englishman.
【高考真题剖析】
（2011?陕西卷）22．I _____ through that bitter period without your generous help．
A．couldn’t have gone B．didn’t go
C．wouldn’t go D．hadn’t gone
答案【A】本题考查虚拟语气。因为有without your generous help．
所以是暗含的虚拟语气。
（2011?福建卷）34．??Pity you missed the lecture on nuclear pollution。
??I it, but I was busy preparing for a job interview．
A．attended B．had attended
C．would attend D．would have attended
答案【D】本题考查虚拟语气。由句中I was busy preparing for a job interview.可判定是与过去的事实相反，所以选择D项。
（2011?全国新课标卷）32．They have arrived at lunchtime but their flight was delayed．
A．will B．can C．must D．should
答案【D】本题考查情态动词should的用法。Should have done表示本应该做而实际未做。Must have done 表示过去一定做了。
（2011?陕西卷）24．?Will you read me a story ,Mummy? --OK．You____ have one if you go to bed as soon as possible．
A．might B．must C．could D．shall
答案【D】本题考查情态动词的基本用法。Shall用于第二、三人称表示说话人“命令、允诺、警告等”语气。
【真题练习】
（09安徽）1. Some people who don’t like to talk much are not necessarily shy；they just be quiet people.
A. must B. may C. should D. would
【答案】B
（09北京）2. One of the few things you ____ say about English people with certainty is that they talk a lot about the weather.
A. need B. must C. should D. can
【答案】B
（09福建）. But for t he help of my English teacher, I the first prize in the English Writing Competition.
A. would not win B. would not have won
C. would win D. would have won
【答案】B 虚拟语气。此处虚拟语气表示与过去事实相反，句子谓语动词用would/should/could/might + have done结构，故选B。
（09湖南）4.? It’s the office! So you know eating is not allowed here.
? Oh, sorry.
A. must B. will C. may D. need
【答案】A 句意为：这是办公室！因此你必须知道吃的不允许带到这里。must表示“绝不”的意思。
（09海南）5. What do you mean, there are only ten tickets? There be twelve
A. should B. would C. will D. shall
【答案】A。 你这是什么意思，只有十张票吗?应该有十二人。should表示“应该，应当”。
（09上海）6. It_____ have been Tom that parked the car here, as he is the only one with a car.
A. may B. can C. must D. should
【答案】C
（09四川）7. ?I don’t care what people think.
?Well, you _______
A. could B. would C . should D. might
【答案】C
【解析】考查情态动词的用法。答话的人提了一个建议??你应该关注别人对你的评价的。should可以用来向别人提建议，所以答案为：C
（09天津）8. This printer is of good quality. If it _______ break down within the first year, we would repair it at our expense.
A. would B. should C. could D. might
【答案】B
（09重庆）9. ?Hi, Tom. Any idea where Jane is?
?She ____in the classroom. I saw her there just now.
A. shall be B. should have been
C. must be D. might have been
【答案】C
（09全国2）10. I can’t leave. She told me that I stay here until she comes back.
A. can B. must C. will D. may
【答案】B
（09江苏）11. He did not regret saying what he did but felt that he it differently.
A. could express B. would express
C. could have expressed D. must have expressed
【答案】C
（10安徽）32. Jack described his father, who _______a brave boy many years ago, as a strong?willed man
A. would be B. would have been
C. must be D. must have been
答案：D.
考点：本题考查情态动词推测用法。
解析：句意为“杰克把他的父亲描述为一个意志坚强的人，他的父亲多年前肯定很勇敢。”用must have been表示对过去事情的肯定推测。
（10湖南）23. You buy a gift, but you can if you want to.
A. must B. mustn't C. have to D. don't have to
答案：D
考点：情态动词
解析：don’t have to 意为“没有必要”，符合语境，句意为：“你没有必要买礼物，但如果你想买的话，你也可以买。”
（10江西）23 I have told you the truth. ______ I keep repeating it?
A Must B Can C May D Will
答案：A
考点：考察情态动词的用法。
解析： must 必须, 一定 can 可以, 能够 may 也许 will 意愿, 倾向性动作, 前半句说我告诉你事实了, 这里用的是现在完成时, 表示过去的动作对现在造成了影响, 既然我已经说了, 我还必须重复一遍吗？
（10山东）25. I_____ have watched that movie ?it’ll give me horrible dreams. [来源:学科网]
A. shouldn’t B. needn’t C. couldn’t D. mustn’t
答案：A
考点：本题考查情态动词的用法。
解析：句意应为“我本来不应该看那部电影的----它会使我做噩梦的。”表示“本来不应该做而做了某事”用shouldn’t have done, 所以A项正确。
10天津）9. Mark have hurried. After driving at top speed, he arrived half an hour early.
A. needn’t B. wouldn’t C. mustn’t D. couldn’t
答案：A.
考点：考查情态动词。
句意：迈克本来不必要那么忙的。这么高速驾驶之后，他早半个小时到达了。
解析：根据后面的语境，提前半个小时到达，说明Mark本来不必那么匆忙，所以用needn’t have done 结构，表示“本来不必要做某事的而实际上做了”。
（10四川）3. ? I take the book out? w_w w. k#s5_u.c o*m
?I'm afraid not.
A. Will B. May C. Must D. Need
答案：B
考点：考查情态动词。[来源:学科网]
解析：表请求可用情态动词can, may, could, might ,表允许用can, may.
句意为：“我可以将这本书带出去吗？”“恐怕不行”。故应选表情请求的情态动词may。正确答案为B
（10全国Ⅰ）29.Just be patient .You ______ expect the world to change so soon .
A. can’t B. needn’t C. may not D. whether
答案：A
句意：耐心一点儿，你不能期望世界变化如此快。
解答：通过选项此题考察情态动词，can't在否定句中可以表示推测，译为不可能，，可以表示能力，译为不能够，也可以表示命令，不允许，但是语气比mustn't弱，具有劝慰的意思，根据句意此题中选择A，can't表示劝慰。
（10江苏）25. ?I haven’t got the reference book yet, but I’ll have a test on the subject next month.
?Don’t worry. You______ have it by Friday.
A. could B. shall C. must D. may
答案：B，
解析：shall在第二人称中表示允诺，还可以表示强制，命令，威胁，警告。还有在法律条文中的要求或规定。
（?陕西）23. May I take this book out of the reading room?
No, you . You read it in here.
A. mightn’t B. won’t C. needn’t D. mustn’t
答案：D
解析：考查情态动词。英语中用could，might表示询问或征求意见的问句中，肯定性应答要用can或may来代替could或might，而may或might征求意见的问句否定应答时要用mustn’t，故本题选D。
（10全国Ⅱ）17.I’m afraid Mr. Harding _________see you now. He’s busy.
A. can’t B. mustn’t C. shouldn’t D .needn’t
答案：A
解析：情态动词考查。结合语境，根据情态动词用于疑问或否定推测时，要用can’t。
（10湖北）79. It’s said that they have swum to the island from the continent, but they ________（不可能做到）because the ocean in between is too wide. (do)
79. 答案：can’t/ couldn’t have done it
考点：情态动词
解析：当要对过去进行肯定的推测时，要用“can’t/couldn’t+have+done”的结构
（10辽宁）26.Doctors say that exercise is important for health, but it _______ be regular exercise.
A．can B．will C．must D．may
答案：C
句意：医生说锻炼对身体重要，但是必须是有规律的锻炼。
解析：考查情态动词。Can一般表示“可能，或能力”；will表示“意志”；may表示“许可，可能”；must表示“必须”。
（10北京）23. ---Good morning. I've got an appointment with Miss Smith in the Personnel Department.
--Ah, good morning. You be Mrs. Peters.
A. might B. must C. would D. can
答案：B
考点:本题考查情态动词在语境中的运用。
解析：第一个说话人说和史密斯小姐有约，那下面的人就回应说，"那您一定就是Mrs. Peters了"因此排除A,C.D
（10浙江）17. “You ____ have a wrong number,” she said. “There’s no one of that name here.”
A. need B. can
C. must D. would
答案：C
考点：情态动词
解析：肯定的猜测，用must
（10上海）29. ---Sorry, Professor Smith. I didn't finish the assignment yesterday.
---Oh, you have done it as yesterday was the deadline.
A. must B. mustn't C. should D. shouldn't
答案：C
考点：本题考查的是虚拟语气
解析：此处表示和过去事实相反的情况，应该用should + have + 过去分词。本来应该做，而未做
（10安徽）26. Bob would have helped us yesterday, but he-_______
A. was busy B. is busy
C. had been busy. D. will be busy [来源:Z&xx&k.Com]
答案：A.
考点：本题考查虚拟语气与时态。
解析：前句表示对过去的虚拟，而but之后表示过去的客观事实，故用一般过去时态。
（10湖南） 29. If he my advice, he wouldn't have lost his job.
A. followed B. should follow
C. had followed D. would follow
答案：C
考点：考查虚拟语气。
解析：根据“wouldn’t have lost”可判断if引导的状语从句表示与过去事实相反的虚拟，故选C项。[来源:学科网ZXXK]
（10天津）15. John went to the hospital alone. If he me about it, I would have gone with him.
A. should tell B. tells C. told D. had told
答案：D.
考点：考查虚拟语气。
句意：约翰独自去了医院。如果他告诉我的话，我会跟他一起去的。
解析：前一句是陈述语气，说明动发生在过去，而且后一句的主句已经是would have gone说明是与过去事实相反的虚拟语气。与之对应的从句结构，应该用had +过去分词。
（10江苏）34. George is going to talk about the geography of his country, but I’d rather he_______ more on its culture.
A. focus B. focused
C. would focus D. had focused
答案：选B
解析：would rather后应用虚拟语气，表示与现在时间相反，用动词的过去式
（?陕西）15. If we ___ the other road, we might have arrived here in time for the meeting.
A. take B. had taken C. took D. have taken
答案：B.
解析：考查虚拟语气。所填词做虚拟语气中条件状语从句的谓语，根据主句的谓语动词形式might have arrived可知题干是与过去事实相反，故所填部分用had+过去分词形式，选B。
（10湖北）76. Mr. Johnson insisted that the problem worthy of attention ________ (讨论) at the meeting. (discuss)
答案：(should) be discussed
考点：虚拟语气
解析：“insist”引导的宾语从句要用虚拟，从句结构是 “should”（可省略）加动词原形，主语 “problem” 是要“被讨论”。
（10北京）34. --The weather has been very hot and dry.
--Yes. If it had rained even a drop, things would be much better now! And my vegetables .
A. wouldn't die B. didn't die
C. had n't died D. wouldn't have died
答案：D
考点：本题考查虚拟语气中对过去的虚拟。
解析：第二个说话人的If条件句是我们选择正确答案的关键。要是当时下雨了，现在的情况就好的多了！我的蔬菜也就不会死了。过去没有下雨，所以我的蔬菜干死了也是发生在过去。而将句子还原则为If it had rained even a drop, my vegetables wouldn't have died.
If+ had done,主句为couldn’t/ shouldn't/ wouldn't have done.
（10浙江）10．Had I known about this computer program, a huge amount of time and energy .
A．would have been savedB．had been saved
C．will be savedD．was saved
答案： A
考点：本题考查虚拟语气。
解析：根据句子的倒装特征判断此处是省略了if的虚拟语气，原形是：If I had known about this computer program, a huge amount of time and energy .故选择A。句意为：如果我早知道这个电脑程序，就可以节省大量的时间和精力了。
（2011?辽宁卷）21．If you __ go, at least wait until the storm is over．【C】
A．can B．may C．must D．will
（2011?北京卷）28．?Where are the children? The dinner’s going to be completely ruined．
?I wish they always late．【A】
A．weren’t B．hadn’t been
C．wouldn’t be D．wouldn’t have been
（2011?北京卷）24．?I don’t really like James．Why did you invite him?
?Don’t worry．He come．He said he wasn’t certain what his plans were．【D】
A．must not B．need not C．would not D．might not
（2011?江西卷）23．_______ be the postman at the door, It’s only sis o’clock．【B】
A．mustn’t B．can’t C．won’t D．needn’t
（2011?四川卷）20．The police still have I found the lost child, but they’re doing about they ．【A】
A．can B．may C．must D．should
（2011?全国II）8．If you____ smoke, please go outside．【C】
A．can B．should C．must D．may（2011?陕西卷）24．?Will you read me a story ,Mummy? 【D】
--OK．You____ have one if you go to bed as soon as possible．
A．might B．must C．could D．shall
（2011?陕西卷）22．I____ through that bitter period without your generous help． 【A】
A．couldn’t have gone B．didn’t go
C．wouldn’t go D．hadn’t gone
（2011?湖南卷）28 ．-----No one ______ be compared with Yao Ming in playing basketball．
------Oh, you are really his big fan． 【A】
A．can B．need C．must D．might
（2011?福建卷）25．------Shall I inform him of the change of the schedule right now?
-----I am afraid you _____,in case he comes late for the meeting ．【B】
A．will B．must C．may D．can
（2011?江苏卷）34．---I left my handbag on the train, but luckily someone gave it to a railway official．
---How unbelievable to get it back! I mean, someone ______ it．【B】
A．will have stolen B．might have stolen
C．should have stolen D．must have stolen
（2011?全国新课标卷）32．They have arrived at lunchtime but their flight was delayed．【D】
A．will B．can C．must D．should
（2011?浙江卷）11．－how is your new babysitter?
－We____ ask for a better one ,All our kids love her so much．【D】
A．should B．might C．mustn't D．couldn't
（2011?重庆卷）25．??Why didn’t you come to Simon’s party last night?
?? I want to ,but my mom simply _________ not let me out so late at night．【C】
A．could B．might C．would D．should
（2011?福建卷）34．??Pity you missed the lecture on nuclear pollution。
??I it, but I was busy preparing for a job interview．【D】
A．attended B．had attended
C．would attend D．would have attended
巩固练习
1.?Are you in a hurry？
?No， in fact I’ve got plenty of time. I ___ wait.
A.must B.need C.may D.should
2.?Someone is knocking at the door. ___ it be Venis？
?No， it ___ be her； she left for New York this morning.
A.Can； mustn’t B.Might； can’t
C.May； doesn’t D.Can； can’t
3.He didn’t agree with me at first， but I ___ persuade him to sign the agreement later.
A.could B.might C.should D.was able to
4.?Is there a movie on in the cinema tonight？
?There___ be. I will phone the cinema and find it out.
A.might B.should C.can D.could
5.You ___ be careful when you cross here ? the traffic lights aren’t working.
A.can B.ought to C.might D.may
6.You ___ out last night. I called you several times， but nobody answered.
A.must have been B.must be
C.might have been D.could be
7.You ___ fail to pass the entrance examination if you don’t study harder.
A.shall B.could C.must D.should
8.When I was studying at Beijing University， I ___ take a walk along the lake every evening.
A.will B.would C.could D.shall
9.The party turned out to be a failure. I would rather ___ it.
A.not have attended B.not attend
C.not to attend D.not to have attended
10.Sir， you ___ be sitting in this seat. It is for women or children only.
A.can’t B.oughtn’t to
C.won’t D.needn’t
11.?Shall I tell Li Ming about the matter？
?No， you ___ . He has known about it already.
A.oughtn’t to B.needn’t
C.shouldn’t D.mustn’t
12.?Must I take a bus？
?No， you ___ . You can walk there.
A.must not B.don’t
C.don’t have to D.had better not to
13.?Why do you make me do so？
?I am sorry that you ___ do such a thing.
A.would B.can C.should D.may
14.?Will you stay for lunch？
?Sorry， I ___ . My brother is coming to see me.
A.mustn’t B.can’t C.needn’t D.won’t
15.What would have happened ___ ， as far as the riverbank？
A.if Bob has walked farther
B.if Bob should walk farther
C.had Bob walked farther
D.should Bob walk farther
16.Oh， Jane， you’ve broken another glass. You ought ___ when you washed it.
A.be careful B.to care
C.have cared D.to have been careful
17.It’s high time we ___ to the theater.
A.will go B.shall go C.are going to D.went
18.?Could I use your telephone？
?Yes， of course you ___ .
A.could B.will C.can D.might
19.It’s strange that they ___ nothing about this matter.
A.should know B.would know
C.had known D.knew
20.?Do you still remember the day when we went to the Great Wall？
?I can’t remember it well， but ___ sometime last autumn？
A.might it be B.could it have been
C.could it be D.must it have been
21.?I can’t get through to the general manager’s office anyhow.
?The line is busy. Someone ___ the telephone.
A.must use B.uses
C.must have been using D.must be using
22.He suggests we ___ to the cinema at once， otherwise we will be late.
A.must go B.go C.will go D.would go
23.If only he ___ me yesterday!
A.had seen B.would see C.should see D.saw
24.If you ___ wait a moment， I’ll go and find our manager.
A.can B.should C.will D.must
25.?It is rather cold here. Shall we light a fire？
?No， we ___ because things are easy to catch fire.
A.won’t B.can’t
C.mustn’t D.needn’t
26.If I ___ you， I ___ more attention to English idioms and phrases.
A.was； shall pay B.am； will pay
C.would be； would pay D.were； would pay
27.?Would you have told him the answer had it been possible？
?I would have， but I ___ so busy then.
A.had been B.were C.was D.would be
28.?Can children swim in this pool？
?Yes. However， at no time ___ they do so by themselves.
A.dare B.should
C.need D.could
29.Kunming is called“Spring City”，but it ___ snow in winter.
A.shall B.can C.must D.might
30.?What’s the matter with you？
?Oh， I’m not feeling well in the stomach. I ___ so much fried fish just now.
A.shouldn’t eat B.mustn’t have eaten
C.shouldn’t have eaten D.mustn’t eat
31.?You look so upset. What’s wrong with you？
?The door ___ . Can you help me？
A.won’t open B.won’t be opened
C.can’t open D.can’t be opened
32.?Mum，I climbed to get the Teddy Bear from the top of the shelf.
?My goodness！You ___ yourself. You mustn’t do that next time.
A.must have hurt B.should have hurt
C.may have hurt D.can have hurt
33.Children under 12 years of age in that country ___ be under adult supervision when he is in a public library.
A.must B.may C.can D.need
34.“The interest ___ be divided into five parts， according to the agreement made by both sides，” declared the judge.
A.may B.should C.must D.shall
35.?I don’t mind telling you what I know.
?You ___ . I’m not asking you for it.
A.mustn’t B.may not C.can’t D.needn’t
36.?Mum，I’ve been studying English since 8 o’clock. ___ I go out and play with Tom for a while？
?No， I’m afraid not. Besides， it’s raining outside now.
A.Can’t B.Wouldn’t
C.Dare not D.Won’t
37.?Who is the girl standing over there？
?Well， if you ___ know， her name is Mabel.
A.may B.can C.must D shall
38.The driver has drunk too much wine and dangerous things ___ happen at any time.
A. should B. can C. must D. need
39.We ___ booked. Look， this restaurant is almost empty.
A. must have B. can’t have
C. should have D. needn’t have
40.Listen! The fire engine is roaring. There ___ be a fire somewhere.
A. should B. must C. will D. ought to
【答案及部分解析】 1～5 CDDAB 6～10 AABAB
11～15 BCCBC 16～20 DDCAB
21～25 DBACC 26～30 DCBBC
31～35 ACADD 36～40 ACADB
1. may表示“可以”。
2. can用在疑问句和否定句中，表示可能性的推测。can’t表示“不可能”。
3. 情态动词can和be able to都可表示能力。当表示“过去成功地做了某事”时，常用was（were） able to。
4. 由下文的I will phone the cinema and find it out可知此处应用might。may或might用在肯定句中，表示可能性的推测。
5. ought to表示劝告。
6. 题意为“我昨天晚上打了几次电话都没有人接，你一定是出去了”。must have done常用来表示对过去发生情况的肯定推测。
7. shall用于第二人称或第三人称，表示说话者的意愿，有命令、警告、威胁、强制、允诺和决心之意。此题用shall，表示“警告”。
8. 情态动词would可以表示过去经常性或习惯性的动作。与used to相比，would不含有“现在已无此习惯”的意义。
9. 题意为“那次聚会以失败告终，我宁愿没参加”。would rather （not）have done表示的是过去发生的情况。
10.由题意可知，此处应用oughtn’t to，表示“不应该”。
11.由he has known about it already可知，此处应用needn’t，表示“没有必要”。
12. don’t have to表示“不必”。
13. should常用在形容词sorry， anxious， happy， delighted等后接的that从句中，表示“竟，会”等意义。
15.had Bob walked farther相当于if Bob had walked farther。在虚拟条件状语从句中，省略if时要把had， should， were等提到句首。
16. ought to have done表示“过去本来应该做某事而事实上并没有做到”。
17. “It’s（high或about） time”后所接从句时，从句谓语动词常用过去式。
18. 问句中情态动词could表示委婉客气。
19. 题意为“他们竟然对此事一无所知，真令人奇怪”。“It’s strange， possible...+that从句”的句型中，从句谓语常用“should+动词原形”。
20. can（could） have done表示对过去发生情况的可能性推测，常用于否定句或疑问句中。
21. must be doing表示对现在正发生情况的肯定推测。
22. suggest， order， demand， request等表示建议或命令等的动词后接宾语从句，从句谓语常用“should（常省略）+动词原形”。
23. if only表示“但愿”。如果表示现在的愿望，句中谓语动词常用过去式；如果表示将来的愿望，句中谓语动词常用“would（could）+动词原形”；如果表示过去的愿望，句中谓语动词常用“had+过去分词”。
24. will表示“愿意”。
25. mustn’t表示“禁止”。
26. 表示与现在的事实相反，从句用一般过去时，主句谓语常用“would，could，should，might+动词原形”。
27. had it been possible相当于if it had been possible。but分句是描述当时的事实，故用一般过去时态。
28. at no time（在任何时候都不）位于句首时，句子应用部分倒装语序。should表示“应该”。
29. 此处用can表示“一时之可能”。
31. The door won’t open. 这门打不开。will表示“功能”，可译为“能，行”。又如：Each classroom will seat 60 students. 每间教室能容纳60名学生。
32. may（might） have done表示对过去发生情况的可能性推测，常用于肯定句中。
33. 题意为：“在那个国家12岁以下的儿童在公共图书馆时必须（must）有成年人监护。”
34. 由judge（法官）一词可断定，此处有强制、命令的语气，故填shall。
36. 此处句意为：“难道我不能（can’t）出去和汤姆玩一会儿吗？”
38. should表示“很可能”。
39. needn’t have done表示“本来不需要做某事而事实上已经做了”。
情态动词和虚拟语气
【2012年高考命题预测】
作为历年高考必考语法点情态动词依旧会是2012年高考的热点。同学们首先应该着重掌握情态动词的基本用法，同时结合情态动词的用法学习虚拟语气。
【概述】情态动词也叫语气动词，有一定的词义，但本身不表示行为或状态，而只是表示说话人对所说动作的看法，认为它“可能”、“应当”、“必要”等。情态动词不能单独作谓语动词，只能和动词原形一起构成谓语动词。英语里的情态动词主要有：can(could), may(might), must, shall, will, would, need, dare, should, ought to。情态动词在任何主语后没有人称和数的变化。除must, need, ought to外，其他情态动词有表示过去时的形式变化：
现在式 过去式
can could
may might
shall should
will would
dare dared
【重难点突破】
一、情态动词
⒈ can 和could
⑴表示能力
can 表示现在或未来的能力，could作为can的过去式，表示过去的“能力”
Whales cannot live on land. 鲸不能生活在陆地上。
Before liberation few workers could support their families.
解放前几乎没有工人能养得起家。
* be able to 与can、could的异同：
◆be able to 可用于多种时态，can和could只用于现在时和过去时。
He will be able to go wi th us this afternoon.
他今天下午能和我们一起去。 （一般将来时）
I haven’t been able to see the difference yet.
我还不能看出区别在哪。（现在完成时）
He thought I would be able to do the work well.
他认为我能把这项工作做好。（过去将来时）
The sick man was soon able to stand up.
病人很快能站立起来。（一般过去时）
◆如果表示过去“能够”、“做到”，“设法干成了某事”，常用was/were able to …来表达（相当于managed to do sth.或succeeded in doing sth.）,而不用could。
We were able to get there before the meeting began.
会前我们终于赶到那里。
◆can间或可用于肯定句，表示理论上的可能性，表示笼统的时间，事物的特征
Anybody who wants to try can be successful.
只要想试，任何人都可能成功。
Scotland can be very warm in September. 九月份苏格兰会很暖和。
（2）、表示许可和请求
在日常生活中，can可以代替may,表示“允许”；could 可以代替can用来表示现在时间的动作，但语气较为婉转，表请求。
☆Can/Could I use your pen?
我可以用一下你的钢笔吗？（表请求）(could 比can更客气，语气更委婉)
Yes, you can.( 回答时不能说成could)
（3）、习惯短语：
cannot…too… 越…越好
cannot but 不得不
You cannot be too careful. 你越仔细越好。
I cannot but do so. 我不得不这样做。
（4）、can 和could 后面接动词的完成式，表示对过去情况的猜测或判断。can常用于疑问句和否定句，而could能用于肯定句，表示一个非事实的或不可能实现的可能性。
You were stupid to go skiing there. You could have broken your leg.
去那里滑雪你真是太傻了，你会摔断腿的。（实际上没有摔断腿）
⑸could have done本来能做而实际未做，表达遗憾的感情色彩
----I stayed at a hotel while in New York.
----Oh, did you? You could have stayed with Jane.
在纽约期间，我无处安身，只好住在旅馆里。
嗷，是吗？你本可以和珍妮住在一起。（表达遗憾的感情色彩）
⒉ may 和might
⑴表示“允许”或“请求对方的允许”，might 比may 语气更客气、更委婉
May/Might I take the book out of the room?
我可以把这本书拿出房间吗？（表请求允许）(might 比may更委婉，更客气)
⑵表示“可能性”
常用于肯定句和否定句，指说话人的猜测，认为某事或许可能发生。might并不表示某事过去可能发生，而是表示一种虚拟语气，指把握性不大，句中可以用may代替，不过may 要比might所表示的可能性要大。
He may/might come. You’d better stay here for a moment.
他或许来，你最好在这儿等他一会儿。
(I am not sure whether he’ll really come.)
I may/might not be back for dinner.
我可能不回来吃饭了。（I’m not sure whether I’ll be back.）
⑶用于祈使句，表“祝愿”
May you both be happy！ 祝你们俩幸福！
May you succeed！ 祝你成功！
⑷习惯搭配：may /might as well 还是…的好
You may as well give him the letter.你还是把信给他为好。
I might as well stay at home tonight. 我今晚还是呆在家里吧。
⑸在表示目的或让步的状语从句中构成谓语
Write to her at once so that she may know in time.
马上给她写信使她及时知道。
⒊ must
⑴表示“必须”、“一定”（现在和未来）
We must finish this before he comes.
我们必须在他回来之前做完这件事。
⑵must 和have to：
◆严格说来，这两个词是有区别的, must表示说话人主观认为的“必须”，而have/has to表示客观的需要，也可译为“不得不”
I really must stop smoking. 我真的该戒烟了。（我认为应该戒）
I have to stop smoking.
我得戒烟了。（可能医生的要求或身体的客观情况使我戒烟）
◆have to 有时态和人称的变化，而must没有
I had to write some letters last night.我昨晚不得不写些信。
I will have to meet Mr. Edward at three o’clock this afternoon.
我必须今天下午三点钟去会见爱德华先生。（将来时态）
◆must not=mustn’t 表示禁止，“不许”，“一定不能”
do not have to =don’t have to “不必”
You don’t have to go now. 你不必现在就走。
◆must 用于疑问句时，肯定回答用must, 否定回答用need not 或don’t have/need to
Must I hand in my paper now? 我必须现在交吗？
Yes, you must. (No, you needn’t. 或No, you don’t have to.)
⑶must用在反意疑问句中
在反意疑问句中，附加部分要和陈述部分的情态动词或主要动词在意思上相呼应，使用情况各有不同：当陈述部分中的must作“必须，一定要”讲时，附加部分用mustn’t 或needn’t; 当must表推测，作“一定是，准是”讲时，附加部分要根据must后的原形动词选用相对应的形式。
He must work hard at English, mustn’t he ?
他必须努力学习英语，是吧？
You must renew the book, needn’t you? 你必须续借这本书，对不对？
He must be a teacher, isn’t he ?他准是一名教师，是吗？（不说mustn’t）
You must have studied English for many years, haven’t you?
你想必学了多年英语，是吗？（不说mustn’t）
He must have arrived here yesterday, didn’t he?
他想必昨天就到了这里，是吗？（不说haven’t）
⑷must表示“偏偏”
The car must break down just when we were about to start off.
我们正要出发时偏偏车又坏了。
4、need 和dare
⑴need 作情态动词，表示“需要”，只用于否定句和疑问句中，无人称和数的变化。
We needn’t go there tomorrow. 我们不必明天去那里。
Need I tell you all the details? 我需要把一切详情告诉你吗？
⑵dare作情态动词，通常用在否定句和疑问句中，无人称和数的变化。
I dare not stand on the chair. 我不敢站在椅子上。
How dare you say such a thing? 你怎么敢说这种话？
⑶need 和dare 也可作行为动词，与一般动词的变化相同。
◆作行为动词（或实义动词）时，need后面接“to + 动词原形”。
Do I need to tell you all the details? 我需要把一切详情告诉你吗？
You didn’t need to come. 你当时没必要来。
◆dare在肯定句中（I dare say除外）和疑问句中，后面都接“to +动词原形”，在否定句中有时带to, 有时不带to, 如：
She dares to go out alone at night. 她晚上敢一人出去。
He did not dare (to ) do so. 他不敢这样做。
⑷惯用语：I dare say 表示“我想”、“大概”。
There’s something wrong with the radio, I dare say.
收音机恐怕有点毛病。
I dare say you are right. 我想你是对的。
⑸ needn’t + have +过去分词
表示过去本来不必做某事而实际上做了，“本不必做…”
You needn’t have come.你本不必来。 (=You didn’t have to come.) （事实上你来了）
He needn’t have waited for me.他本不必等我。（=He didn’t have to wait for me.） (事实上他等我了)
⒌will 和would
⑴表意愿、决心
在陈述句或在条件状语从句中，wil l 和would用于任何人称。
I will finish my lesson even if I have to stay up all night.
即使我整夜不睡觉我也一定要把功课做完。
If you will allow me, I’ll go with you.如果你愿意的话，我将跟你去。
⑵ would 可表示过去的习惯动作
He would sit there for hours sometimes, doing nothing at all.
他有时候长时间地坐在那里，什么事都不做。
Every morning I would go for a long walk.
我每天早晨都会走很长的一段距离。
⑶ 表示询问对方的意愿或向对方提出请求,此时，would比will 的语气更婉转
Will you please pass me the magazine? 请你把杂志递给我好吗？
Won’t you come over? 请到这边来好吗？
⑷ would 与like连用，表请求、提议，比will更婉转礼貌，这时would表示的是现在时间并非过去时
Would you like to leave your telephone number?
请留下你的电话号码好吗？
⑸ will 可以表示现在或当前的习惯性、经常性、倾向性。常译成“惯于”、“总是”
No matter what you say, he will always argue with you.
不管你说什么，他总是和你争论。
A wise man changes his mind, a fool never will.
聪明人能随机应变，傻瓜是不会的。
Water will boil at 100℃. 水在摄氏100度时总是要沸腾的。
⒍shall
⑴用于第一、第三人称疑问句，表示说话人征询对方意见或请求指示
Where shall I put my bag? 我把包放在哪里好呢？
Shall he come in or wait outside? 让他进来还是在外边等着？
⑵用于第二、第三人称，表示意愿、期望、允诺、命令、强制、警告、威胁等语气
You shall keep your room in order. 你须保持房间整洁。（表命令）
He shall be sorry for it one day, I tell you.
有一天他会后悔的，我告诉你。（表警告）
⒎should
⑴表示责任、义务、建议、劝告，用于各人称
You should study every day. 你们应该每天学习。（表责任）
You should always think of others before yourself.
你应当首先想到别人。（表劝告）
⑵表推测、可能，暗含很大的可能
I think he should be home now. 我想他现在应该在家。
You should know his address.你应该知道他的住址。
⑶should + have + 过去分词 表过去本应完成而未完成的动作
shouldn’t + have + 过去分词 表示过去发生了不应发生的动作
He should have arrived by this time.他本应这个时候到了。（其实未到）
⑷用在why , how开头的疑问句中或that 引导的从句中表达说话人感情色彩，表达意外和不满，“竟，竟会”
I’m sorry that you should think so badly of me.
你竟把我想得那么坏，我感到遗憾。
⑸用于if 引导的从句中，构成虚拟语气
If he should drop in, give him my message.
他如果来访，就把我的条交给他。
⑹用于建议、命令等的从句中，构成虚拟语气
We demanded that our wages should be raised. 我们要求提高工资。
⑺在It is necessary/ important/strange that…中：谓语动词常用should + do, 或只用动词原形，构成虚拟语气
It is necessary that he should be sent there at once.
派他马上去那是必要的。
⒏ ought to
⑴ ought to 和should差不多，都表“应当”，在很多情况下可通用，但也有细微的差别：在表示因责任、义务等该做的事情时，常用ought to ，在表示某件事宜于做时，多用should.
You are his father. You ought to take care of him.你是他父亲，应当管他。
⑵表推测，暗含很大的可能
If we start now, we ought to be able to get there in time.
如果我们现在动身，我们应当能准时到达。
⑶ ought to + have +过去分词 表过去本应做但实际上没做的事
oughtn’t to + have +过去分词 表示过去本不该做但实际上做了事
I ought to have written him a letter.我本应给他写封信。（实际上没写）
I oughtn’t to have written him a letter.我本不该给他写信。[来源:学_科_网]
★表示推测的情态动词用法归纳：
⒈ 肯定句中：
must (一定)，may (可能)，might/could (也许，或许) 其语气的肯定程度依次递减。其中，might 和could并非过去时态，只是语气较为委婉或可能性较小
⑴对当前行为、情况或状态的推测： must /may /might /could + do/be
He must/may/might/could be in the reading room.
★他肯定/可能/也许在阅览室里。
⑵对此时此刻正在进行的动作的推测：
must /may/ might/ could + be doing 想必/可能正在…
He must /may/ might/ could be watching TV at this time.
他此时一定/可能/或许在看电视。
⑶对过去发生的事情的推测：
must /may /might /could + have +过去分词 想必/可能已经…
You look very tired. You must have stayed up last night.
看上去你很疲劳，你昨晚一定熬夜了。
You may have read about it in the papers.
你可能在报上已读到这件事了。
⑷过去的一段时间内一直在进行的动作：
must/may /might/ could + have + been +doing 想必/可能一直在…
He may have been waiting for us for an hour. 他可能等我们一小时了。⒉ 否定句中：
can/could not 不可能，想必不会
may/might not 可能不
⑴对当前行为、情况或状态的推测：
can/could not +动词原形 不可能，想必不会
may/might not +动词原形 可能不
He may not be busy now. 也许他现在不忙。
He can’t be in the reading room. I saw him on the playground just now.
他不可能在阅览室里，我刚看到他在操场上。
⑵对此时此刻正在进行的动作的推测：
can/could not + be doing 不可能，想必不会在干某事
may/might not + be doing 可能没在干某事
They can’t be telling the truth. 他们不可能在说真话。
They may not be telling the truth. 他们可能没在说真话。
⑶对过去发生的事情的推测：
can/could not + have +过去分词 不可能，想必不会做过某事
may/might not + have +过去分词 可能没干过某事
He may not have achieved all his aims. But his effort is a good one.
他可能 没达到他的全部目的，但他还是认真做了努力的。
⑷过去的一段时间内一直在进行的动作：
can’t /couldn’t/may not have been doing
He can’t have been waiting for us so long.他不可能等我们那么长时间。
⒊疑问句中：
常用can/could来表示说话人的猜疑、怀疑或不肯定的语气
⑴对当前行为、情况或状态的推测：
can/could + 主语+ do/be
Where can he be now? 他现在会在哪里呢？
⑵对此 时此刻正在进行的动作的推测： can/could +主语+ be doing
It’s so late. Can Tom be reading? 这么晚了，汤姆还在看书吗？
⑶对过去发生的事情的推测： can/could +主语+have done
Can she have told a lie? 她会不会说谎了？
（2011?辽宁卷）21．If you __ go, at least wait until the storm is over．【C】
A．can B．may C．must D．will
（2011?江西卷）23．___ be the postman at the door, It’s only sis o’clock．【B】
A．mustn’t B．can’t C．won’t D．needn’t
（2011?四川卷）20．The police still have I found the lost child, but they’re doing about they ．【A】
A．can B．may C．must D．should
二、虚拟语气
1、虚拟语气的重点是：
1）．一些常见的虚拟语气的句型或结构。
2)．虚拟语气的特殊形式，即用来表示要求、建议、命令、提议、意愿等的主语从句、宾语从句、表语从句和同位语从句中的虚拟形式。
3)．主从句表示不同的时间概念、事实或假设情况，从而交错成为复合虚拟语气。
4)．含蓄条件句中的虚拟语气的表示愿望的虚拟形式。
2、虚拟语气的常见类型和句型
（1）由wish引起的表示愿望的虚拟语气
A．用wish表示对现在的愿望时，它所引起的宾语从句中谓语动词形式为：过去式（be动词用were）。
B．用wish表示对将来的愿望时，它所引起的宾语从句中谓语动词形式为：would, could, might+ 动词原形。
C．wish用于对过去的事实表示一种不可能实现的愿望时，宾语从句中的谓语动词形式为：had+动词过去分词或could, would + have +动词过去分词。
The picture exhibition bored me to death; I wish I had not gone to it.
（2）would (had) rather, would as soon, would sooner和would prefer所引起的从句中要求用过去式表示当时或将来的情况，用过去完成时表示过去的情况，表示希望或婉转的责备。
I’d rather you posted the letter right away.
我倒希望你把这封信立刻寄出去。
（3）由连接词in case, so that ,unless, lest ,for fear that引起的状语从句中，谓语动词要用虚拟形式，即should(might, would)+动词原形，
She put a blanket over the baby for fear that he should catch cold.
她在那个婴儿身上盖上了毯子以免他着凉。
The bad man was put in the soft-padded cell lest he injure himself.
(4) 虚拟语气在条件句中的应用
表示与现在事实相反：If + 从句主语 + 动词的过去式…，主语+should/ would/ could/ might + 动词原形…（be 一般用were）
表示与过去事实相反：If + 从句主语 + had + 过去分词…，主语+should/ would/ could/ might +have +过去分词…
表示与将来事实可能相反： If + 从句主语 + ①动词的过去式…，②should +动词原形…， ③were to +动词原形…， 主语 + should/ would/ could/ might + 动词原形…
If it had not been for his help(=but for his help),we would not have succeeded.
(5) 虚拟语气用于as if（though）引起的方式状语从句和表语从句中，其动词形式与wish宾语从句的形式相同。
She often laughs spontaneously, and her good humor breaks out as brightly as if it were a part of the sunshine above.
她常常发出发自内心的微笑，而且她那美好的情绪像天上一道明亮的阳光一样，常常流露出来。
They talked as if they had been friends for years.
他们交谈着，就好像他们是我年的老朋友一样。
(6)其它各种句型, as though, suppose, had rather, supposing, if only等等
If I were in a movie, then it would be about time that I buried my head in my hands for a cry.
二、特殊形式的虚拟语气
虚拟语气的特殊形式，即用来表示要求、建议、命令、提议、意愿等的主语从句、宾语从句、表语从句和同位语从句中的虚拟形式，其虚拟语气的构成往往是由should(可省略)+动词原形that从句。
A、 用于表示意愿、建议、命令、提议、请求等动词后的that宾语从句中，这类动词有：
ask要求 advise建议 arrange安排 beg请求 command命令 decide决定 demand要求 desire渴望
determine决定 insist坚持 intend打算 maintain坚持主张 move建议，动员 propose提议 object反对 order命令 prefer建议 require 需要 request要求 resolve下决心 recommend推荐 suggest建议 stipulate约定，规定 urge强调，促进 vote公认，提议 decree颁布（法令） pray请求
注意：这类动词后面除了可接that虚拟句以外，也可以接doing或者to do…来表达，一般情况下，意思没有什么差别。
She advised that we should keep the gate locked.（ 书面体）
She advised us to keep the gate locked.（口语）
She advised keeping the gate locked.(较随便)
B、用于It is+形容词或过去分词+主语从句中，这类形容词或分词有：
advisable合理的 decided决定的 crucial关键的 appropriate恰当的 determined决定的 commanded命令的 arranged安排的 essential紧要的，基本的 complied遵照 anxious焦急的 imperative迫切的 important重要的 desirable合意的 better较好的，更好 insistent坚持的 desired想要 asked请求 keen渴望的 incredible难以置信的 adamant坚定不移的 natural自然的 insisted坚持 necessary必要的 suggested建议 urgent紧迫的 ordered命令 shocked震惊的 vital极其重要的 possible可能的 strange 奇怪的 preferable （好一点） proposed提议 requested要求的 required要求的 recommended推荐 resolved决定的 probable（可能的） pity可惜，憾事 shame遗憾
注意：这类形容词后面除了可接that虚拟句以外，也可以for…to do… 来表达，一般情况下，意思没有什么差别。
It is essential that he should be prepared for this.
It is essential for him to be prepared for this.
C．用于由表示建议、要求、命令、请示等含义的名词引导的表语从句和同位语从句中，这类名词常见的有：
advice忠告 decision决定 demand要求 desire要求、愿望 insistence坚持 motion提议 necessity必要性 order命令 preference偏爱 proposal提议 pray恳求 recommendation推荐 request要求 requirement要求 resolution决心 suggestion劝告、忠告
This is their resolution that extra-curriculum activities be made part of their school life.
这是他们的决议：要使得课外活动成为他们学校生活的一部分。
The motion that the remark of the last speaker be expunged from the record.该提议要求把最后一个发言的人的从记录上除掉。
三、混合虚拟语气
有时主句和从句的谓语动词指不同的时间，这时需要用混合虚拟语气。一般来说，在这种情况下，主从句谓语动词指代的时间不同，所以我们又可以错综时间条件句，在这种虚拟情况，动词形式应根据实际情况灵活使用，在做这些题目时候尤其要注意每道题目的提示语：时间状语。绝大多数情况下，从句或者主句都有相关的时间状语，这是我解题的关键。
If you that late movie last night, you wouldn’t be so sleepy.
A. haven’t watched B. didn’t watch
C. hadn’t watched D. wouldn’t have watched 答案选C。
Many dead would now be alive if they have not attempted to return for something.
Had Paul received six more votes in the last election, he would be our chairman now.
混合虚拟语气还有一种情况就是事实和虚拟假设的混合句，这样的句子不仅仅是时间的不同，而重要是事实和假设的混合。
I would have gone to visit him in the hospital had it been at all possible, but I was fully occupied the whole of last week.
该句前半部分是假设虚拟，而后半部分是事实的陈述。
Your math instructor would have been happy to give you a mak e-up examination had you gone and explained that your parents were ill at the time.
该句前半句用的是假设虚拟，后半句主句也用的是假设虚拟（如果你去并且解释的话），但是后半句的从句用的是事实语气，因为“父母病了”是客观事实，故不需要用虚拟形式had been。
四、含蓄虚拟条件句
含蓄条件句是指句中没有明显的虚拟条件句，而是利用其他手段来暗示存在虚拟条件。但是这类隐含式虚拟条件句往往都可以转化为if引导的条件句。常来表示含蓄虚拟条件的手段有：
（1）介词或介词短语，如but for, but that, without, in case of, under more favorable condition等。
the leadership of the party, we could not be living a happy today.=If there hadn’t been the leadership of the party, we could not be living a happy today.
A. In spite of B. But for C. Because of D. As for 答案选B。
But that she was afraid, she would have said no.
(2)连词，如：so that, unless, in case, supposing, lest, provided(倘若……)，for fear that(唯恐)，in order that, on condition that, if only(要是……就好了)等。
She listened carefully in order that she might discover exactly what he wanted.=if she listened carefully ,she might discover exactly what he wanted.
If only I had more money, I could buy a car.
(注：lest, for fear that 和 in case 引起的从句中谓语动词多用should+动词原形，但可以不用虚拟语气，而用动词的陈述语气形式。)例如：
The foreign teacher spoke slowly in case we misunderstood him. 这位外籍教师说得很慢以免我们听不懂。
Care must be taken in using this method lest overflow should occur.在使用此法时要小心谨慎，以免会发生溢流现象。
（3）通过上下文及内在含义，句中往往有but, otherwise, unfortunately等类似转折词。
I thought the children when we returned home, but they were still awake.
A. were sleeping B. would be sleeping C. had been sleeping D. would sleep选择 B。
(4)形容词及其比较级
A more careful person would not have made so many mistakes.
A less conscientious man wouldn’t have tried so hard to get this job done.
(5)分词短语
Having known in time, we might have prevented the accident.
Born ten days earlier, the boy could have seen his late father.
(6)动词不定式短语。一般intended/meant/hoped/wished/planned 或 was/were+不定式完成式或had intended/meant/planned/hoped/wished/+不定式一般式表示虚拟。
I intended I should call on you, but I was busy at that time.
To hear him speak French, you would take him for an Englishman.
【高考真题剖析】
（2011?陕西卷）22．I _____ through that bitter period without your generous help．
A．couldn’t have gone B．didn’t go
C．wouldn’t go D．hadn’t gone
答案【A】本题考查虚拟语气。因为有without your generous help．
所以是暗含的虚拟语气。
（2011?福建卷）34．??Pity you missed the lecture on nuclear pollution。
??I it, but I was busy preparing for a job interview．
A．attended B．had attended
C．would attend D．would have attended
答案【D】本题考查虚拟语气。由句中I was busy preparing for a job interview.可判定是与过去的事实相反，所以选择D项。
（2011?全国新课标卷）32．They have arrived at lunchtime but their flight was delayed．
A．will B．can C．must D．should
答案【D】本题考查情态动词should的用法。Should have done表示本应该做而实际未做。Must have done 表示过去一定做了。
（2011?陕西卷）24．?Will you read me a story ,Mummy? --OK．You____ have one if you go to bed as soon as possible．
A．might B．must C．could D．shall
答案【D】本题考查情态动词的基本用法。Shall用于第二、三人称表示说话人“命令、允诺、警告等”语气。
【真题练习】
（09安徽）1. Some people who don’t like to talk much are not necessarily shy；they just be quiet people.
A. must B. may C. should D. would
【答案】B
（09北京）2. One of the few things you ____ say about English people with certainty is that they talk a lot about the weather.
A. need B. must C. should D. can
【答案】B
（09福建）. But for t he help of my English teacher, I the first prize in the English Writing Competition.
A. would not win B. would not have won
C. would win D. would have won
【答案】B 虚拟语气。此处虚拟语气表示与过去事实相反，句子谓语动词用would/should/could/might + have done结构，故选B。
（09湖南）4.? It’s the office! So you know eating is not allowed here.
? Oh, sorry.
A. must B. will C. may D. need
【答案】A 句意为：这是办公室！因此你必须知道吃的不允许带到这里。must表示“绝不”的意思。
（09海南）5. What do you mean, there are only ten tickets? There be twelve
A. should B. would C. will D. shall
【答案】A。 你这是什么意思，只有十张票吗?应该有十二人。should表示“应该，应当”。
（09上海）6. It_____ have been Tom that parked the car here, as he is the only one with a car.
A. may B. can C. must D. should
【答案】C
（09四川）7. ?I don’t care what people think.
?Well, you _______
A. could B. would C . should D. might
【答案】C
【解析】考查情态动词的用法。答话的人提了一个建议??你应该关注别人对你的评价的。should可以用来向别人提建议，所以答案为：C
（09天津）8. This printer is of good quality. If it _______ break down within the first year, we would repair it at our expense.
A. would B. should C. could D. might
【答案】B
（09重庆）9. ?Hi, Tom. Any idea where Jane is?
?She ____in the classroom. I saw her there just now.
A. shall be B. should have been
C. must be D. might have been
【答案】C
（09全国2）10. I can’t leave. She told me that I stay here until she comes back.
A. can B. must C. will D. may
【答案】B
（09江苏）11. He did not regret saying what he did but felt that he it differently.
A. could express B. would express
C. could have expressed D. must have expressed
【答案】C
（10安徽）32. Jack described his father, who _______a brave boy many years ago, as a strong?willed man
A. would be B. would have been
C. must be D. must have been
答案：D.
考点：本题考查情态动词推测用法。
解析：句意为“杰克把他的父亲描述为一个意志坚强的人，他的父亲多年前肯定很勇敢。”用must have been表示对过去事情的肯定推测。
（10湖南）23. You buy a gift, but you can if you want to.
A. must B. mustn't C. have to D. don't have to
答案：D
考点：情态动词
解析：don’t have to 意为“没有必要”，符合语境，句意为：“你没有必要买礼物，但如果你想买的话，你也可以买。”
（10江西）23 I have told you the truth. ______ I keep repeating it?
A Must B Can C May D Will
答案：A
考点：考察情态动词的用法。
解析： must 必须, 一定 can 可以, 能够 may 也许 will 意愿, 倾向性动作, 前半句说我告诉你事实了, 这里用的是现在完成时, 表示过去的动作对现在造成了影响, 既然我已经说了, 我还必须重复一遍吗？
（10山东）25. I_____ have watched that movie ?it’ll give me horrible dreams. [来源:学科网]
A. shouldn’t B. needn’t C. couldn’t D. mustn’t
答案：A
考点：本题考查情态动词的用法。
解析：句意应为“我本来不应该看那部电影的----它会使我做噩梦的。”表示“本来不应该做而做了某事”用shouldn’t have done, 所以A项正确。
10天津）9. Mark have hurried. After driving at top speed, he arrived half an hour early.
A. needn’t B. wouldn’t C. mustn’t D. couldn’t
答案：A.
考点：考查情态动词。
句意：迈克本来不必要那么忙的。这么高速驾驶之后，他早半个小时到达了。
解析：根据后面的语境，提前半个小时到达，说明Mark本来不必那么匆忙，所以用needn’t have done 结构，表示“本来不必要做某事的而实际上做了”。
（10四川）3. ? I take the book out? w_w w. k#s5_u.c o*m
?I'm afraid not.
A. Will B. May C. Must D. Need
答案：B
考点：考查情态动词。[来源:学科网]
解析：表请求可用情态动词can, may, could, might ,表允许用can, may.
句意为：“我可以将这本书带出去吗？”“恐怕不行”。故应选表情请求的情态动词may。正确答案为B
（10全国Ⅰ）29.Just be patient .You ______ expect the world to change so soon .
A. can’t B. needn’t C. may not D. whether
答案：A
句意：耐心一点儿，你不能期望世界变化如此快。
解答：通过选项此题考察情态动词，can't在否定句中可以表示推测，译为不可能，，可以表示能力，译为不能够，也可以表示命令，不允许，但是语气比mustn't弱，具有劝慰的意思，根据句意此题中选择A，can't表示劝慰。
（10江苏）25. ?I haven’t got the reference book yet, but I’ll have a test on the subject next month.
?Don’t worry. You______ have it by Friday.
A. could B. shall C. must D. may
答案：B，
解析：shall在第二人称中表示允诺，还可以表示强制，命令，威胁，警告。还有在法律条文中的要求或规定。
（?陕西）23. May I take this book out of the reading room?
No, you . You read it in here.
A. mightn’t B. won’t C. needn’t D. mustn’t
答案：D
解析：考查情态动词。英语中用could，might表示询问或征求意见的问句中，肯定性应答要用can或may来代替could或might，而may或might征求意见的问句否定应答时要用mustn’t，故本题选D。
（10全国Ⅱ）17.I’m afraid Mr. Harding _________see you now. He’s busy.
A. can’t B. mustn’t C. shouldn’t D .needn’t
答案：A
解析：情态动词考查。结合语境，根据情态动词用于疑问或否定推测时，要用can’t。
（10湖北）79. It’s said that they have swum to the island from the continent, but they ________（不可能做到）because the ocean in between is too wide. (do)
79. 答案：can’t/ couldn’t have done it
考点：情态动词
解析：当要对过去进行肯定的推测时，要用“can’t/couldn’t+have+done”的结构
（10辽宁）26.Doctors say that exercise is important for health, but it _______ be regular exercise.
A．can B．will C．must D．may
答案：C
句意：医生说锻炼对身体重要，但是必须是有规律的锻炼。
解析：考查情态动词。Can一般表示“可能，或能力”；will表示“意志”；may表示“许可，可能”；must表示“必须”。
（10北京）23. ---Good morning. I've got an appointment with Miss Smith in the Personnel Department.
--Ah, good morning. You be Mrs. Peters.
A. might B. must C. would D. can
答案：B
考点:本题考查情态动词在语境中的运用。
解析：第一个说话人说和史密斯小姐有约，那下面的人就回应说，"那您一定就是Mrs. Peters了"因此排除A,C.D
（10浙江）17. “You ____ have a wrong number,” she said. “There’s no one of that name here.”
A. need B. can
C. must D. would
答案：C
考点：情态动词
解析：肯定的猜测，用must
（10上海）29. ---Sorry, Professor Smith. I didn't finish the assignment yesterday.
---Oh, you have done it as yesterday was the deadline.
A. must B. mustn't C. should D. shouldn't
答案：C
考点：本题考查的是虚拟语气
解析：此处表示和过去事实相反的情况，应该用should + have + 过去分词。本来应该做，而未做
（10安徽）26. Bob would have helped us yesterday, but he-_______
A. was busy B. is busy
C. had been busy. D. will be busy [来源:Z&xx&k.Com]
答案：A.
考点：本题考查虚拟语气与时态。
解析：前句表示对过去的虚拟，而but之后表示过去的客观事实，故用一般过去时态。
（10湖南） 29. If he my advice, he wouldn't have lost his job.
A. followed B. should follow
C. had followed D. would follow
答案：C
考点：考查虚拟语气。
解析：根据“wouldn’t have lost”可判断if引导的状语从句表示与过去事实相反的虚拟，故选C项。[来源:学科网ZXXK]
（10天津）15. John went to the hospital alone. If he me about it, I would have gone with him.
A. should tell B. tells C. told D. had told
答案：D.
考点：考查虚拟语气。
句意：约翰独自去了医院。如果他告诉我的话，我会跟他一起去的。
解析：前一句是陈述语气，说明动发生在过去，而且后一句的主句已经是would have gone说明是与过去事实相反的虚拟语气。与之对应的从句结构，应该用had +过去分词。
（10江苏）34. George is going to talk about the geography of his country, but I’d rather he_______ more on its culture.
A. focus B. focused
C. would focus D. had focused
答案：选B
解析：would rather后应用虚拟语气，表示与现在时间相反，用动词的过去式
（?陕西）15. If we ___ the other road, we might have arrived here in time for the meeting.
A. take B. had taken C. took D. have taken
答案：B.
解析：考查虚拟语气。所填词做虚拟语气中条件状语从句的谓语，根据主句的谓语动词形式might have arrived可知题干是与过去事实相反，故所填部分用had+过去分词形式，选B。
（10湖北）76. Mr. Johnson insisted that the problem worthy of attention ________ (讨论) at the meeting. (discuss)
答案：(should) be discussed
考点：虚拟语气
解析：“insist”引导的宾语从句要用虚拟，从句结构是 “should”（可省略）加动词原形，主语 “problem” 是要“被讨论”。
（10北京）34. --The weather has been very hot and dry.
--Yes. If it had rained even a drop, things would be much better now! And my vegetables .
A. wouldn't die B. didn't die
C. had n't died D. wouldn't have died
答案：D
考点：本题考查虚拟语气中对过去的虚拟。
解析：第二个说话人的If条件句是我们选择正确答案的关键。要是当时下雨了，现在的情况就好的多了！我的蔬菜也就不会死了。过去没有下雨，所以我的蔬菜干死了也是发生在过去。而将句子还原则为If it had rained even a drop, my vegetables wouldn't have died.
If+ had done,主句为couldn’t/ shouldn't/ wouldn't have done.
（10浙江）10．Had I known about this computer program, a huge amount of time and energy .
A．would have been savedB．had been saved
C．will be savedD．was saved
答案： A
考点：本题考查虚拟语气。
解析：根据句子的倒装特征判断此处是省略了if的虚拟语气，原形是：If I had known about this computer program, a huge amount of time and energy .故选择A。句意为：如果我早知道这个电脑程序，就可以节省大量的时间和精力了。
（2011?辽宁卷）21．If you __ go, at least wait until the storm is over．【C】
A．can B．may C．must D．will
（2011?北京卷）28．?Where are the children? The dinner’s going to be completely ruined．
?I wish they always late．【A】
A．weren’t B．hadn’t been
C．wouldn’t be D．wouldn’t have been
（2011?北京卷）24．?I don’t really like James．Why did you invite him?
?Don’t worry．He come．He said he wasn’t certain what his plans were．【D】
A．must not B．need not C．would not D．might not
（2011?江西卷）23．_______ be the postman at the door, It’s only sis o’clock．【B】
A．mustn’t B．can’t C．won’t D．needn’t
（2011?四川卷）20．The police still have I found the lost child, but they’re doing about they ．【A】
A．can B．may C．must D．should
（2011?全国II）8．If you____ smoke, please go outside．【C】
A．can B．should C．must D．may（2011?陕西卷）24．?Will you read me a story ,Mummy? 【D】
--OK．You____ have one if you go to bed as soon as possible．
A．might B．must C．could D．shall
（2011?陕西卷）22．I____ through that bitter period without your generous help． 【A】
A．couldn’t have gone B．didn’t go
C．wouldn’t go D．hadn’t gone
（2011?湖南卷）28 ．-----No one ______ be compared with Yao Ming in playing basketball．
------Oh, you are really his big fan． 【A】
A．can B．need C．must D．might
（2011?福建卷）25．------Shall I inform him of the change of the schedule right now?
-----I am afraid you _____,in case he comes late for the meeting ．【B】
A．will B．must C．may D．can
（2011?江苏卷）34．---I left my handbag on the train, but luckily someone gave it to a railway official．
---How unbelievable to get it back! I mean, someone ______ it．【B】
A．will have stolen B．might have stolen
C．should have stolen D．must have stolen
（2011?全国新课标卷）32．They have arrived at lunchtime but their flight was delayed．【D】
A．will B．can C．must D．should
（2011?浙江卷）11．－how is your new babysitter?
－We____ ask for a better one ,All our kids love her so much．【D】
A．should B．might C．mustn't D．couldn't
（2011?重庆卷）25．??Why didn’t you come to Simon’s party last night?
?? I want to ,but my mom simply _________ not let me out so late at night．【C】
A．could B．might C．would D．should
（2011?福建卷）34．??Pity you missed the lecture on nuclear pollution。
??I it, but I was busy preparing for a job interview．【D】
A．attended B．had attended
C．would attend D．would have attended
巩固练习
1.?Are you in a hurry？
?No， in fact I’ve got plenty of time. I ___ wait.
A.must B.need C.may D.should
2.?Someone is knocking at the door. ___ it be Venis？
?No， it ___ be her； she left for New York this morning.
A.Can； mustn’t B.Might； can’t
C.May； doesn’t D.Can； can’t
3.He didn’t agree with me at first， but I ___ persuade him to sign the agreement later.
A.could B.might C.should D.was able to
4.?Is there a movie on in the cinema tonight？
?There___ be. I will phone the cinema and find it out.
A.might B.should C.can D.could
5.You ___ be careful when you cross here ? the traffic lights aren’t working.
A.can B.ought to C.might D.may
6.You ___ out last night. I called you several times， but nobody answered.
A.must have been B.must be
C.might have been D.could be
7.You ___ fail to pass the entrance examination if you don’t study harder.
A.shall B.could C.must D.should
8.When I was studying at Beijing University， I ___ take a walk along the lake every evening.
A.will B.would C.could D.shall
9.The party turned out to be a failure. I would rather ___ it.
A.not have attended B.not attend
C.not to attend D.not to have attended
10.Sir， you ___ be sitting in this seat. It is for women or children only.
A.can’t B.oughtn’t to
C.won’t D.needn’t
11.?Shall I tell Li Ming about the matter？
?No， you ___ . He has known about it already.
A.oughtn’t to B.needn’t
C.shouldn’t D.mustn’t
12.?Must I take a bus？
?No， you ___ . You can walk there.
A.must not B.don’t
C.don’t have to D.had better not to
13.?Why do you make me do so？
?I am sorry that you ___ do such a thing.
A.would B.can C.should D.may
14.?Will you stay for lunch？
?Sorry， I ___ . My brother is coming to see me.
A.mustn’t B.can’t C.needn’t D.won’t
15.What would have happened ___ ， as far as the riverbank？
A.if Bob has walked farther
B.if Bob should walk farther
C.had Bob walked farther
D.should Bob walk farther
16.Oh， Jane， you’ve broken another glass. You ought ___ when you washed it.
A.be careful B.to care
C.have cared D.to have been careful
17.It’s high time we ___ to the theater.
A.will go B.shall go C.are going to D.went
18.?Could I use your telephone？
?Yes， of course you ___ .
A.could B.will C.can D.might
19.It’s strange that they ___ nothing about this matter.
A.should know B.would know
C.had known D.knew
20.?Do you still remember the day when we went to the Great Wall？
?I can’t remember it well， but ___ sometime last autumn？
A.might it be B.could it have been
C.could it be D.must it have been
21.?I can’t get through to the general manager’s office anyhow.
?The line is busy. Someone ___ the telephone.
A.must use B.uses
C.must have been using D.must be using
22.He suggests we ___ to the cinema at once， otherwise we will be late.
A.must go B.go C.will go D.would go
23.If only he ___ me yesterday!
A.had seen B.would see C.should see D.saw
24.If you ___ wait a moment， I’ll go and find our manager.
A.can B.should C.will D.must
25.?It is rather cold here. Shall we light a fire？
?No， we ___ because things are easy to catch fire.
A.won’t B.can’t
C.mustn’t D.needn’t
26.If I ___ you， I ___ more attention to English idioms and phrases.
A.was； shall pay B.am； will pay
C.would be； would pay D.were； would pay
27.?Would you have told him the answer had it been possible？
?I would have， but I ___ so busy then.
A.had been B.were C.was D.would be
28.?Can children swim in this pool？
?Yes. However， at no time ___ they do so by themselves.
A.dare B.should
C.need D.could
29.Kunming is called“Spring City”，but it ___ snow in winter.
A.shall B.can C.must D.might
30.?What’s the matter with you？
?Oh， I’m not feeling well in the stomach. I ___ so much fried fish just now.
A.shouldn’t eat B.mustn’t have eaten
C.shouldn’t have eaten D.mustn’t eat
31.?You look so upset. What’s wrong with you？
?The door ___ . Can you help me？
A.won’t open B.won’t be opened
C.can’t open D.can’t be opened
32.?Mum，I climbed to get the Teddy Bear from the top of the shelf.
?My goodness！You ___ yourself. You mustn’t do that next time.
A.must have hurt B.should have hurt
C.may have hurt D.can have hurt
33.Children under 12 years of age in that country ___ be under adult supervision when he is in a public library.
A.must B.may C.can D.need
34.“The interest ___ be divided into five parts， according to the agreement made by both sides，” declared the judge.
A.may B.should C.must D.shall
35.?I don’t mind telling you what I know.
?You ___ . I’m not asking you for it.
A.mustn’t B.may not C.can’t D.needn’t
36.?Mum，I’ve been studying English since 8 o’clock. ___ I go out and play with Tom for a while？
?No， I’m afraid not. Besides， it’s raining outside now.
A.Can’t B.Wouldn’t
C.Dare not D.Won’t
37.?Who is the girl standing over there？
?Well， if you ___ know， her name is Mabel.
A.may B.can C.must D shall
38.The driver has drunk too much wine and dangerous things ___ happen at any time.
A. should B. can C. must D. need
39.We ___ booked. Look， this restaurant is almost empty.
A. must have B. can’t have
C. should have D. needn’t have
40.Listen! The fire engine is roaring. There ___ be a fire somewhere.
A. should B. must C. will D. ought to
【答案及部分解析】 1～5 CDDAB 6～10 AABAB
11～15 BCCBC 16～20 DDCAB
21～25 DBACC 26～30 DCBBC
31～35 ACADD 36～40 ACADB
1. may表示“可以”。
2. can用在疑问句和否定句中，表示可能性的推测。can’t表示“不可能”。
3. 情态动词can和be able to都可表示能力。当表示“过去成功地做了某事”时，常用was（were） able to。
4. 由下文的I will phone the cinema and find it out可知此处应用might。may或might用在肯定句中，表示可能性的推测。
5. ought to表示劝告。
6. 题意为“我昨天晚上打了几次电话都没有人接，你一定是出去了”。must have done常用来表示对过去发生情况的肯定推测。
7. shall用于第二人称或第三人称，表示说话者的意愿，有命令、警告、威胁、强制、允诺和决心之意。此题用shall，表示“警告”。
8. 情态动词would可以表示过去经常性或习惯性的动作。与used to相比，would不含有“现在已无此习惯”的意义。
9. 题意为“那次聚会以失败告终，我宁愿没参加”。would rather （not）have done表示的是过去发生的情况。
10.由题意可知，此处应用oughtn’t to，表示“不应该”。
11.由he has known about it already可知，此处应用needn’t，表示“没有必要”。
12. don’t have to表示“不必”。
13. should常用在形容词sorry， anxious， happy， delighted等后接的that从句中，表示“竟，会”等意义。
15.had Bob walked farther相当于if Bob had walked farther。在虚拟条件状语从句中，省略if时要把had， should， were等提到句首。
16. ought to have done表示“过去本来应该做某事而事实上并没有做到”。
17. “It’s（high或about） time”后所接从句时，从句谓语动词常用过去式。
18. 问句中情态动词could表示委婉客气。
19. 题意为“他们竟然对此事一无所知，真令人奇怪”。“It’s strange， possible...+that从句”的句型中，从句谓语常用“should+动词原形”。
20. can（could） have done表示对过去发生情况的可能性推测，常用于否定句或疑问句中。
21. must be doing表示对现在正发生情况的肯定推测。
22. suggest， order， demand， request等表示建议或命令等的动词后接宾语从句，从句谓语常用“should（常省略）+动词原形”。
23. if only表示“但愿”。如果表示现在的愿望，句中谓语动词常用过去式；如果表示将来的愿望，句中谓语动词常用“would（could）+动词原形”；如果表示过去的愿望，句中谓语动词常用“had+过去分词”。
24. will表示“愿意”。
25. mustn’t表示“禁止”。
26. 表示与现在的事实相反，从句用一般过去时，主句谓语常用“would，could，should，might+动词原形”。
27. had it been possible相当于if it had been possible。but分句是描述当时的事实，故用一般过去时态。
28. at no time（在任何时候都不）位于句首时，句子应用部分倒装语序。should表示“应该”。
29. 此处用can表示“一时之可能”。
31. The door won’t open. 这门打不开。will表示“功能”，可译为“能，行”。又如：Each classroom will seat 60 students. 每间教室能容纳60名学生。
32. may（might） have done表示对过去发生情况的可能性推测，常用于肯定句中。
33. 题意为：“在那个国家12岁以下的儿童在公共图书馆时必须（must）有成年人监护。”
34. 由judge（法官）一词可断定，此处有强制、命令的语气，故填shall。
36. 此处句意为：“难道我不能（can’t）出去和汤姆玩一会儿吗？”
38. should表示“很可能”。
39. needn’t have done表示“本来不需要做某事而事实上已经做了”。
