高中英语高考解密08 情态动词和虚拟语气（教师版） -2021年高考英语高频考点解密

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解密08情态动词和虚拟语气

考点详解



【考纲解读】
1. 考生应掌握can, could, may, might, must, will, would, shall, should, ought to, need, dare, be able to, used to等情态动词的基本用法。
2. 考生应掌握虚拟语气在非真实条件句、名词性从句及其他句型中的运用。
【命题趋势】
情态动词和虚拟语气为中学英语考纲要求的内容，并且是高考内容中的难点之一。预计在以后的高考中，可能会对情态动词和虚拟语气进行考查，且还可能通过虚拟语气形式考查某种时态的某个形式。

考向1 情态动词


一、 can, could 与 be able to
1. 表示能力（体力、知识、技能）。
☞Can you lift this heavy box?（体力）
☞Mary can speak three languages.（知识）
☞Can you skate?（技能） 此时可用be able to代替。
can只有一般现在时和一般过去式；而be able to则有更多的时态。
☞I’ll not be able to come this afternoon.
当表示“经过努力才得以做成功某事”时应用be able to，不能用can。如：
☞He was able to go to the party yesterday evening in spite of the heavy rain.
2. 表示请求和允许。
☞——Can I go now?
——Yes, you can. / No, you can’t. 此时可与may互换。
在疑问句中还可用could, might代替，不是过去式，只是语气更委婉，不能用于肯定句和答语中。
☞——Could I come to see you tomorrow?
—— Yes, you can. ( No, I’m afraid not. )
3. 表示客观可能性（客观原因形成的能力）。
☞They’ve changed the timetable, so we can go by bus instead. This hall can hold 500 people at least.
4. 表示推测（惊讶、怀疑、不相信的态度），用于疑问句、否定句和感叹句中。
☞Can this be true?
☞This can’t be done by him. How can this be true?

1. (2020·天津卷·单项填空)Jim says we ______ stay in his house as long as we leave it clean and tidy .
A. must B. can C. need D. should
【答案】B
【解析】考查情态动词。句意:吉姆说我们可以住在他的房子里，只要我们保持它干净整洁。A. must必须；B. can能，可以；C. need需要；D. should应该。根据后面的“as long as we leave it clean and tidy”可知，Jim许可我们待在他的房子里，即:我们”能，可以”待在他的房子里。故选B。
2. (2018·北京卷·单项填空) In today’s information age, the loss of data _________ cause serious problems for a company.
A. need B. should C. can D. must
【参考答案】C
【答案解析】考查情态动词。句意：在今天的信息时代，数据的丢失有时会对一个公司造成严重的问题。数据丢失造成严重问题是客观上会发生的情况，即“客观可能性”，故该空应用情态动词can。C选项正确。其余情态动词均没有该用法。need需要；should应该，竟然；must必须，肯定。
3. (2017·北京卷·单项填空)Samuel, the tallest boy in our class, ________ easily reach the books on the top shelf.
A. must B. should
C. can D. need
【参考答案】C　
【答案解析】考查情态动词。can表示能力，意为“能够”。故答案为C。句意：塞缪尔——我们班个子最高的男孩——能够轻松地够到架子顶层上的书。
二、 may, might
1. 表示请求和允许。
might比 may语气更委婉，而不是过去式。否定回答时可用can’t 或mustn’t，表示“不可以，禁止”。 ☞——Might/ May I smoke in this room?
——No, you mustn’t.
☞——May/Might I take this book out of the room?
——Yes, you can. (No, you can’t / mustn’t. )
用May I...？征徇对方许可时比较正式和客气，而用Can I...？在口语中更常见。
2. 用于祈使句，表示祝愿。
☞May you succeed!

might为may的过去式，但也可以代替may，语气较为婉转客气或更加不肯定。
He might not come today. 今天他也许不来了。(语气不肯定)
You might also get a headache when you work too hard. 当你工作太努力时，你也可能患头痛。


You feel all the training a waste of time, but I’m a hundred percent sure later you’ll be grateful you did it.
A. should B. need
C. shall D. may
【参考答案】D
【答案解析】句意：你可能觉得所有的训练都是浪费时间，但是我有100%的把握你以后会感激它的。should应该；need需要；shall将会；may（不确定）可能。所以选D。
三、 must, have to
1. 表示必须、必要
☞You must come in time.
在回答引出的问句时，如果是否定的，不能用mustn’t（禁止，不准），而用needn’t, don’t have to（不必）。
☞——Must we hand in our exercise books today?
——Yes, you must. /No, you don’t have to / you needn’t.
2. must是说话人的主观看法，而have to则强调客观需要。
must只有一般现在时， have to 有更多的时态形式。
☞I really must go now.
☞I had to work when I was your age.
3. must表示推测、可能性（只用于肯定的陈述句）
☞You’re Tom’s good friend, so you must know what he likes best.
☞Your mother must be waiting for you now.

①must开头的疑问句，其否定回答通常用don’t have to或needn’t。而不用mustn’t。
—Must I finish my homework first? 我必须先完成作业吗？
—No, you don’t have to/ needn’t. 不，你不必。
②can和must在表推测时，can一般用于否定句中，而must 常用于肯定句中。
It can not be Li Lei. 那个人不可能是李磊。
It must be Li Lei. 那个人肯定是李磊。

1.—Can’t you stay a little longer?
—It’s getting late. I really _________go now, My daughter is home alone.
A .may B .can
C . must D .dare
【参考答案】C
【答案解析】句意：——你不能再多待会儿吗?——很晚了，我必须得走了。我女儿一个人在家。A. may可能，可以，也许； can能，会；C. must必须，必然要，必定会；D. dare敢，胆敢。结合句意，故选C。
2. You __________be careful with the camera. It costs!
A .must B. may
C. can D. will
【参考答案】A
【答案解析】考查情态动词。根据下文的it costs可知，照相机很昂贵，可推断此处是说，你一定要非常小心对待照相机。故选A 。may可能；can能够，有时会；will会，愿意。
四、 dare, need
1. dare作情态动词用时, 常用于疑问句、否定句和条件从句中, 过去式形式为dared。
☞How dare you say I’m unfair?
☞He daren’t speak English before such a crowd, dare he?
☞If we dared not go there that day，we couldn’t get the beautiful flowers.
2. need 作情态动词用时, 常用于疑问句、否定句。在肯定句中一般用must, have to, ought to, should代替。 ☞You needn’t come so early.
☞—Need I finish the work today?
—Yes, you must. / No, you needn’t.
注意：
dare和 need作实义动词用时，有人称、时态和数的变化。在肯定句
中，dare后面常接带to的不定式。在疑问句和否定句中，dare后面可
接带to或不带to的不定式。而need后面只能接带to的不定式。
☞I dare to swim across this river.
☞He doesn’t dare (to) answer.
☞He needs to finish his homework today.
五、 shall, should
1. shall 用于第一人称，征求对方的意见。
☞What shall we do this evening?
2. shall 用于第二、三人称，表示说话人给对方的命令、警告、允诺或威胁。
☞You shall fail if you don’t work hard.(警告)
☞He shall have the book when I finish it.(允诺)
☞He shall be punished.(威胁)
3．should表示义务、职责等，意为＂应该＂。
☞You should be strict with yourself as an officer.
作为一名官员，你应该严格要求自己。
六、 will, would
1. 表示请求、建议等，would更委婉。
☞Will / Would you pass me the ball, please?
2. 表示意志、愿望和决心。
☞I will never do that again.
☞They asked him if he would go abroad.
3. would表示过去反复发生的动作或某种倾向。would表示过去习惯时比used to正式，且没有“现已无此习
惯”的含义。
☞During the vacation, he would visit me every other day.
☞The wound would not heal.

1. （2019.天津卷Ⅰ）The professor warned the students that on no account ______ use mobile phones in the class. A. should they B. they should C. dare they D. they dare
【参考答案】A
【试题解析】考查特殊句式和情态动词。句意： 教授警告学生们，在他的课堂上绝不要使用手机。在that 引导的宾语从句中，表否定意义的介词短语on no account 位于句首，后面的主、谓需要用部分倒装结构，故排除B项和D项；根据句意可知此处应该用情态动词should，故选A。
2.(2018·新课标II卷·短文改错) As kid, I loved to watch cartoons, but no matter how many times I asked to them, my parents would not to let me.
【参考答案】删除let前的to　
【答案解析】would后跟动词原形，故把to删除。
七、 should, ought to
1. should, ought to表示“应该”，ought to表示义务或责任，比should语气重。
☞I should help her because she is in trouble.
☞You ought to take care of the baby.
2. 表示劝告、建议和命令。should, ought to可通用，但在疑问句中常用should。
☞You should / ought to go to class right away.
☞Should I open the window?
3. 表示推测 should , ought to (客观推测), must(主观推测)。
☞He must be home by now. (断定他已到家)
☞He ought to/should be home by now.(不太肯定)
☞This is where the oil must be.(直爽)
☞This is where the oil ought to/should be.(含蓄)

考向2 情态动词+have done



情态动词＋have done
用法
must have done
一定做过某事，其否定形式为can’t/couldn’t have done
can/could have done
(1)本来能够做但却未做
(2)可能做过某事
can’t/couldn’t have done
不可能做过某事
may/might have done
或许/可能做过某事
should/ought to have done
本该做但却未做，其否定形式表示本不该做但却做了
needn’t have done
做了本没有必要做的事情
1.＂must have done＂
☞表示对过去事情的肯定推测，译成＂一定做过某事＂，该结构只用于肯定句。
☞It must have rained last night, for the ground is wet. 昨晚一定下雨了，因为地面还是湿的。
☞You must have been mad to speak to the servant. 你和仆人说话，一定是发疯了。
2.＂can’t have done＂
表示对过去事情的否定推测，译成＂不可能做过某事＂。
☞Mr Smith can’t have gone to Beijing, for I saw him in the library just now.
史密斯先生不可能去北京了，我刚才还在图书馆见过他。
☞Mary can’t have stolen your money. She has gone home.
玛丽不可能偷你的钱，她回家去了。
3.＂can have done＂
☞表示对过去行为的怀疑，用于疑问句，译成＂可能做过……吗？＂。
☞There is no light in the room. Can they have gone out?
屋里没有灯，他们可能出去了吗？
☞There is nowhere to find them. Where can they have gone?
到处找不到他们，他们可能到什么地方去呢？
4.＂could have done＂
是虚拟语气，表示对过去事情的假设，意思是本来能够做某事而没有做。
☞He could have passed the exam, but he was too careless. 本来他能够通过考试，但是他太粗心。
5.＂may have done＂
表示对发生过的事情的推测，意思是＂可能已经＂或＂也许已经＂，用于肯定句中。
☞—What has happened to George? 乔治发生了什么事？
—I don’t know. He may have got lost. 我不知道，他可能迷路了。
6.＂might have done＂
表示对过去事情的推测，might与may意思相同，但可能性更小。多用于虚拟语气结构中。
☞She might have achieved greater progress, if you had given her more chances.
如果你多给她点机会，她可能已经取得了更大的成绩。
7.＂would have done＂
虚拟语气，表示对过去事情的假设，意思是＂本来会……＂。
☞I would have told you all about the boy’s story, but you didn’t ask me.
我本来会告诉你这个小男孩的故事，但是你没有问我。
8.＂should have done＂
意思是＂本来应该做某事，而实际没做＂。＂shouldn’t+have+done＂表示本来不应该做某事，而实际做了。含有指责对方或自责的含义。
☞Tom, you are too lazy. The work should have been finished yesterday.
汤姆，你太懒惰了，这项工作本来应该昨天就做完的。
☞Look, Tom is crying. I shouldn’t have been so harsh on him.
看，汤姆哭了，我本不应该对他如此严厉的。
9.＂ought to have done＂
表示过去应该做而实际并没有做，译成＂理应做……＂，往往表示遗憾。与＂should have done＂用法基本一样。
☞I ought to have gone home last Sunday. 我理应上星期日回家。
☞You ought not to have given him more help. 你不应该帮助他那么多。
10.＂need have done＂
表示本来需要做某事而实际没有做。＂needn’t have done＂则表示＂本来不需要做某事而实际做了＂
☞I needn’t have bought so much wine — only five people came.
我本来没有必要买这么多酒，只来了五个人。
☞He need have hurried to the station. In that case, he wouldn’t have missed the train.
他本来需要快点去车站的，那样的话，他就不会误了火车。

—Sorry, Mum! I failed the job interview again.
—Oh, it’s too bad. You _____________ have made full preparations.
A. must B. can
C. would D. should
【参考答案】D
【答案解析】考查情态动词+have done结构。句意：——对不起，妈妈，我面试又失败了。——噢，那太糟糕了，你应该做好充分准备的。A.must必须；B.can可以；C.would将会；D.should应该。can have done＂表示对过去行为的怀疑，用于疑问句，译成＂可能做过……吗？＂；could have done表示对过去事情的假设，意思是本来能够做某事而没有做；must have done＂表示对过去事情的肯定推测，译成＂一定做过某事＂，该结构只用于肯定句；should have done＂的意思是＂本来应该做某事，而实际没做。故选D。

难点剖析



情态动词表猜测的用法：
一、can / could用于表推测的用法
(1) 从使用句型上看，can 通常只用于否定句或疑问句，一般不用于肯定句，而could 可用于肯定句、否定
句和疑问句。两者没有时间上的差别，只是could 比 can 更委婉，更不确定。如：
☞It can’t [couldn’t] be true. 那不可能是真的。
☞What can [could] they be doing? 他们会在干什么呢?
☞We could go there this summer. 今年夏天我们可能要去那儿。
注：can 有时也用于肯定句中表示推测，主要用于表示理论上的可能性(即从理论上看是可能的，但实际未必会发生)，或表示“有时”之意。如：
☞Even experienced teachers can make mistakes. 即使是有经验的教师也可能出错。
☞She can be very unpleasant. 她有时很令人讨厌。
(2) 从时间关系看，对现在或将来情况作推测，后接动词原形；对正在进行的情况作推测，后接 be doing 结
构；对过去情况作推测，后接动词完成式。如：
☞He could have gone home. 他可能已经回家了。
☞He can’t [couldn’t] have understood. 他不可能理解了。
☞Why does he know this? Can [Could] someone have told him about it?
他怎么知道? 会是哪个人告诉他了吗?
(3) “could+完成式”除表示对过去的推测外，还有以下重要用法：
①表示过去没有实现的可能性，常译为“本来可以”。如：
☞I could have lent you the money．Why didn’t you ask me?
我本来可以借这笔钱给你的。你为什么不向我提出?
②用来委婉地责备某人过去应该做某事而没有去做，常译为“本来应该”。如：
☞You could have helped him. 你本来应该帮助他的。
③表示“差点儿就要”。如：
☞I could have died laughing. 我差点儿笑死了。
二、 may / might用于表推测的用法
表示推测，两者都可用，只是 might 比 may 语气更不确定，表示的可能性更小。
(1) 在句型使用方面：两者均可用于肯定句和否定句，但用于疑问句时，may通常不用于句首，但可用于疑
问句的句中（如特殊疑问句等），而might尽管可以用于疑问句的句首，但不算普通，通常会改用其他
句式（如用could等）。如：
☞He may [might] know the answer. 他可能知道答案。
☞He may [might] not believe you. 他可能不会相信你。
☞And who may [might] she be? 那么她会是哪一位呢？
(2) 从时间关系看，对现在或将来情况作推测，后接动词原形；对正在进行的情况作推测，后接 be doing 结
构；对过去情况作推测，后接动词完成式。如：
☞He may [might] tell his wife. 他也许会告诉他妻子。
☞He may [might] be writing a letter. 他可能在写信。
☞She may [might] have read it in the papers. 她可能在报上已读到过此事。
(3)“might+完成式”除表示对过去的推测外，还有以下重要用法：
① 表示过去某事可能发生而实际上却并没发生。如：
☞It was really very dangerous. I might have killed myself. 那真的是太危险了，我差点没命了。
☞A lot of men died who might have been saved．很多人本来可以获救的却死了。
② 表示委婉的批评或责备。如：
☞You might have made greater progress. 你的进步本来可更大一些的。
☞You might at least have answered my letter. 你至少可以回我一封信嘛。
三、must表示推测的用法
must 表示很有把握的推测，其意为“一定会”“肯定会”，只用于肯定句，一般不用于否定句或疑问句。表示对现在或未来的情况作推测，后接动词原形；表示对过去情况的推测，接动词完成式。如：
☞I must be the happiest woman on earth! 我一定是世界上最幸福的女人了。
☞No, he must be lying. 不，他一定在撒谎
☞He must have mistaken my meaning. 他一定误会了我的意思。

考向3 虚拟语气


一、虚拟语气在条件句中的应用
包含条件从句的句子称为条件句。条件句分为两类：一类是真实条件句，一类是虚拟条件句。
如果假设的情况很可能发生，就用真实条件句。
☞If he has time, he wil come. 如果他有时间，他会来的。
☞He won’t succeed unless we plan well. 他不会成功的，除非我们计划好。
如果假设的情况发生的可能性不大，则用虚拟条件句。虚拟条件句分为三种，见下表：
假设情况
条件从句的谓语形式
主句的谓语形式
与现在事实相反
过去式（be的过去式常用were）
would/should/might/could + 动词原形
与将来事实相反
(1) 过去式
(2)should + 动词原形
(3)were to + 动词原形
would/should/might/could + 动词原形
与过去事实相反
过去完成时（had + 过去分词）
would/should/might/could + 过去分词
☞If he had time now，he would(could，might)go with you.
要是他现在有时间，他会和你一起去的。(与现在事实相反)
☞If you had come a few minutes earlier，you would(could，might) have met the famous singer.
如果你早来几分钟，你就会见到那个著名歌手了。(与过去事实相反)
☞If it were to snow this evening，they would not go out.
如果今天晚上下雪，他们就不会出去。(与将来事实相反)
二、几种特殊的虚拟条件从句
1．省略if形式的虚拟语气
在if虚拟条件句中，若省略if，则将should，were，had前置，构成主谓倒装句式。
☞Had I worked harder，I would have succeeded.
如果我当时努力学习的话，我就会成功的。
☞Were she my daughter(Should she be my daughter)，I wouldn't allow her to study abroad.
如果她是我的女儿的话，我就不让她出国学习了。
2．混合虚拟语气
若主句和从句所表示的时间不一致，就构成了混合虚拟语气或错综虚拟语气，此时，主句和从句的时态形式根据实际的时间概念来定。
☞If she had followed the doctor's words，she would feel better now.
如果当初她听从了医生的建议，现在就会好多了。
3．含蓄虚拟语气
有时候假设的条件不是通过条件从句表达，而是隐含在某些介词短语中，如without...，连词but for，otherwise，or等中。
☞Without music(＝If there were no music)，the world would be dull.
世界若无音乐将会很枯燥。
☞I'm really very busy，otherwise I would certainly go there with you.(otherwise＝if I were not so busy)
我真的是太忙了，不然我就会同你一道去了。
三、虚拟语气在宾语从句中的应用
1. 动词wish后的宾语从句。
表示现在的情况，从句谓语用过去式；表示过去的情况，从句谓语用过去完成式；表示将来的情况，从句谓语用＂would/ should/could/might + 动词原形＂。
☞I wish I were ten years younger now. 我希望我现在年轻十岁。
☞I wish I had met him yesterday. 我昨天能遇到他就好了。
☞I wish I would be a scientist. 我希望将来成为科学家。

1. (2020·江苏卷·单项填空)28. If I hadn’t been faced with so many barriers, I _____where I am.
A. won’t be B. wouldn’t have been C. wouldn’t be D. shouldn’t have been
【答案】C
【解析】考查虚拟语气。句意：如果我没有面对那么多的障碍，我现在就不会在这里。分析句子成分可知，此处是错综时间虚拟语气，根据空后where I am可知，此处是与现在事实相反的假设，主句谓语动词应使用would/could/might/should+do。故选C。
2. (2018·江苏卷·单项填空)There is a good social life in the village, and I wish I _______ a second chance to become more involved.
A. had B. will have
C. would have had D. have had
【参考答案】A
【答案解析】考查虚拟语气。句意：在这个村里有很好的社交生活，并且我希望我再有机会去更多的参与。本题考查wish引导的宾语从句，表示与现在事实相反的愿望，所以从句用一般过去时。故选A。
2. 在表示请求、建议、命令、要求等动词后的宾语从句中，谓语用＂should + 动词原形＂，should可省略。 常见的这类动词有：suggest，recommend， insist， order， require， advise， demand， command， ask， request，propose等。
☞He suggested that we (should) be here in time. 他建议我们及时到那儿。
☞The doctor advised that he (should) change his job. 医生劝他换工作。

1.(2018·江苏卷·单项填空) It’s strange that he _______ have taken the books without the owner’s permission.
A. would B. should
C. could D. might
【参考答案】B
【答案解析】考查虚拟语气。句意：真奇怪，他竟然没有主人的允许就拿走了这些书。在句型”It is important/necessary/strange/impossible/natural that...”中，其中由that引导的主语从句通常用“should+动词原形”这样的虚拟语气，其中的should可以省略。故选B。
2.（2016·全国新课标卷II·短文改错）Some classmates suggest we can go to places of interest nearby.
【参考答案】删除can或can改为should
【答案解析】考查虚拟语气。动词suggest作为建议讲的时候，后面的宾语从句要使用虚拟语气＂（should+）动词原形＂，所以本句可以删除can或can改为should。
3. 在would rather后的宾语从句中，谓语常用过去式来表示现在或将来的情况，用过去完成式表示过去的情况。
☞I would rather you told me the truth. 我愿意你跟我讲真话。
☞I would rather you had been present. 我倒愿意你当时在场。
4．在＂It is (about/high) time＋that从句＂中，谓语动词常用过去式或＂should＋动词原形＂表示虚拟语气，注意should不可省略。
☞It’s high time that we devoted ourselves to environmental protection.
是我们致力于环境保护的时候了。
5．as if，as though引导的表语从句和方式状语从句中常用虚拟语气，与现在事实相反用一般过去时；与过去事实相反用过去完成时。
☞They talked and talked as if they would never meet again.
他们谈啊谈好像永远不会再见面一样。
6．if only引导的感叹句中，用虚拟语气表示愿望。
☞Look at the trouble we’re in.If only we had taken our teacher’s advice！
看看我们所处的困境，要是我们接受老师的建议就好了！

1. （2019.天津卷Ⅰ）The workers were not better organized, otherwise they ______the task in half the time.
A. Accomplished B. had accomplished C. would accomplish D. would have accomplished
【参考答案】B
【试题解析】考查虚拟语气。工人没有被更好地组织起来，否则他们用一半时间就能完成任务。表示对过去的虚拟，需要would/could/might/should have done的形式，故选D项。
1.（2017•江苏卷） _______ not for the support of the teachers, the student could not overcome her difficulty.
A. It were B. Were it
C. It was D. Was it
【参考答案】B
【试题解析】考查虚拟语气和倒装。虚拟语气中，be动词统一用were；虚拟语气的省略形式主要是把if省略，同时把were/should/had提前，即Were /Should/ Had I...，故选B。句意：要不是老师们的支持，该学生是无法克服她自己的困难的。
2.（2017•天津卷） —Do you have Betty’s phone number?
—Yes. Otherwise, I ______able to reach her yesterday.
A. hadn’t been B. wouldn’t have been
C. weren’t D. wouldn’t be
【参考答案】 B
【试题解析】句意：——你有贝蒂的电话号码吗？——有。否则我昨天就联系不到她了。根据标志词otherwise，否则相当于一个条件状语从句：If I hadn't have her phone number，即对过去的虚拟的条件状语从句，可以判断出主句用wouldn't have done表示对过去情况的虚拟，故选B。

难点剖析



错综时间条件句的虚拟语气
当条件状语从句表示的行为和主句表示的行为所发生的时间不一致时，被称为＂错综时间条件句＂，动词的形式要根据它所表示的时间做出相应的调整。
☞If you had followed the doctor’s advice，you would be better now.
如果你当时听医生建议的话，你现在就好多了。

1.（2018·天津卷·单项填空）If we ___________the flight yesterday, we would be enjoying our holiday on the beach
A. had caught B. caught
C. have caught D. would catch
【答案】A
【解析】考查虚拟语气。句意：如果我们昨天赶上飞机的话，现在我们正在海滩享受我们的假日了。根据时间状语yesterday可知，从句表示与过去事实相反，故用had + v-ed。故选A。
【名师点睛】本题考查虚拟语气。虚拟语气重要做题原则：根据题干中主句或从句中动词形式判断所考查的动词的虚拟时间，一般要保持一致，但要注意错综时间虚拟语气要根据各自所表示的虚拟时间做出调整。本题就是错综条件虚拟语气，从句与过去事实相反，故用had + v-ed，主句与现在事实相反。
2.（2016·江苏卷·单项填空）If it_________ for his invitation the other day, I should not be here now.
A. had not been B. should not be
C. were not to be D. should not have been
【参考答案】A
【答案解析】本句属于错综条件句的虚拟语气。if从句表示与过去事实相反，所以使用过去完成时，主句表示与现在事实相反，所以使用＂情态动词+动词原形＂。句意：如果不是因为前几天他的邀请，我现在就不会在这里了。故A正确。
3. (2015·天津)I wish I ______ at my sister’s wedding last Tuesday, but I was on a business trip in New York then.
A. will be B. would be C. have been D. had been
【参考答案】D
【试题解析】句意：上个周二我本希望参加我姐姐的婚礼，但那时我在纽约出差。本题考查wish引导的宾语从句，表示与过去事实相反的愿望，从句用had + 过去分词。根据句意可知选D。

检测训练



题组一 基础过关
I. 用括号内所给词的适当形式填空
1．I wish that I______________(go) with you to see the film last night.
2．Without electricity，our life____________(be) quite different today.
3．I am a poor man now. If I________(have) money，I______________(buy) a large house.
4．If she had been more careful，she____________________(not make) these mistakes in the exam.
5．I think people__________________(believe) my story if I were not so young.
6．The man insisted that he____________(do) his best and________________(not blame) for the failure.
7．But for the rain，we____________(have) a pleasant journey the other day.
8．If I ________(am) you，I would give that patient a hug.
9．It is raining so heavily. If the rain____________________(stop) this afternoon，we could go out for a walk.
10．All the doctors in the hospital insisted that he__________(be) badly wounded and that he___________(operate)
on at once.
11．How I wish every family________(have) a large house with a beautiful garden.
12．If everyone in the country________(know) first aid，many lives would be saved.
13．Tom wishes that he ______________(study) business instead of history when he was in university.
14．—John went to the hospital alone.
—If he________________(tell) me about it，I would have gone with him.
15．My father was strict. He requested that I__________________(not watch) television on this week nights.
【答案】
1. had gone 2. would be 3. had；would buy 4. wouldn’t have made
5. would believe 6. had done；not be blamed 7. would have had
8. were 9. were to stop/should stop/stopped 10. was；(should) be operated
11. had 12. knew 13. had studied 14. had told 15. (should) not watch
Ⅱ. 用适当的情态动词填空
1. Can you help me? I _________ never understand this.
2. ___________ you tell me what time it is, please?
3. Henry ________ walk when he was one year old.
4. We are going for a walk. _________ you like to join us?
5. Tom, you ___________ leave your clothes on the floor like this.
6. The road is wet. It __________ have rained last night.
7. He has waited outside for half an hour. ___________ he come in?
8. These flowers have died. You _____________ have watered them.
9. __________ she be ten years old next month?
10. I ___________ have hurt your feelings but it was not my intention.
【答案】
1. can 2. Could/Can 3. could 4. Would 5. mustn’t
6. must 7. Shall 8. should 9. Will 10. may
题组二 真题在线
1.(2017·天津) My room is a mess, but I ________clean it before I go out tonight. I can do it in the morning.
A. daren't B. shouldn't
C. needn't D. mustn't
【答案】C　
【解析】 考查情态动词。根据“I can do it in the morning.”可知现在没必要打扫房间。故选C项。needn't不必；daren't不敢；shouldn't不应该；mustn't不准，禁止。句意：我的房间很乱，不过今晚在我出去之前，我没必要打扫它。我可以在(明天)早晨打扫。
2. (2016·天津) It was really annoying; I ________ get access to the data bank you had recommended.
A. wouldn’t B. couldn’t
C. shouldn’t D. needn’t
【答案】B
【解析】句意：这真是令人生气的；我不能进入你推荐的数据库。wouldn’t不愿意；couldn’t不能；shouldn’t不应该；needn’t不必。故选B。
3.(2016·浙江)George _________ too far . His coffee is still warm .
A. must have gone B. might have gone
C. can’t have gone D. needn’t have gone
【答案】C
【答案】句意：乔治不可能走得太远了。他的咖啡仍然是温的。can’t have done是对过去的否定推测；must have done过去一定做了某事；might have done过去可能做了某事；needn’t have done过去本不必做某事。故选C。
4.（2015 • 重庆）You _________ be Carol. You haven’t changed a bit after all these years.
A. must B. can
C. will D. shall
【答案】D
【解析】句意：你肯定是卡罗，这些年你一点也没有变化。must表示对现在的肯定推测。
5. (2017·天津)—Do you have Betty's phone number?
—Yes. Otherwise, I ________ able to reach her yesterday.
A. hadn't been B. wouldn't have been
C. weren't D. wouldn't be
【答案】B
【解析】考查虚拟语气。由空前的otherwise可知应用虚拟语气，再结合句意可知此处表示与过去事实相反，谓语动词用would have done，故选B项。句意：＂你有贝蒂的电话号码吗？＂＂有。不然的话，我昨天就不会联系上她了。＂
6.(2016·浙江)Had the governments and scientists not worked together , AIDS-related deaths _______ since their highest in 2005.
A. had not fallen B. would not fall
C. did not fall D. would not have fallen
【答案】D
【解析】句意：如果政府和科学家不共同努力，艾滋病相关的死亡就不会从2005年的最高点下降。使用虚拟语气， if条件句用的had done，而且省略it，将had提前，主句用would have done表示对过去情况的虚拟。故选D。
7.(2016·北京)Why didn’t you tell me about your trouble last week? If you ________ me, I could have helped.
A. told B. had told
C. were to tell D. would tell
【答案】B
【解析】考查虚拟语气。句意：你上周为什么没有告诉我你遇到的麻烦？如果你告诉我的话，我就可以帮你了。根据第一句可知，这里是对过去发生的事情进行虚拟，if条件句的时态应该用过去完成时，故选B。
8. (2015·安徽)It is lucky we booked a room, or we ______nowhere to stay now.
A. had B. had had
C. would have D. would have had
【答案】C
【解析】句意：我们很幸运地订到了房间，否则的话，我们现在就会无处可去了。or引导含蓄虚拟条件句，or后面是主句，相当于if we hadn’t booked a room, we would have nowhere to stay now.，根据
　　　＂now＂可知，是对现在进行虚拟，因此用would+动词原形，故选C。
题组三 名校模拟
I. 单项填空
1. Lucas failed his driving test again. ________ harder, he ________the test now.
A. If he practiced; would pass
B. Had he practiced; would pass
C. Did he follow; would have passed
D. Should he practice; would have passed
【答案】B
【解析】考查虚拟语气。句意：Lucas驾照考试又失败了，如果他更加努力地练习，现在他就通过考试了。根据语境可知，从句表示与过去事实相反的虚拟语气，省略if，had提前使用倒装句。主句表示与现在事实相反的虚拟语气，谓语动词用would+原形动词。故选B。
2. If we________ a table in advance, we wouldn't be standing here in the long queue.
A. reserve B. reserved
C. have reserved D. had reserved
【答案】D
【解析】考查虚拟语气。句意：如果我们事先预定了一张桌子，我们就不会站在这长长的队伍里了。根据句意可知，从句是对过去的虚拟，与过去事实相反，所以从句中应使用过去完成时；主句与现在事实相反，使用would/ could/ might/ should do…结果。故选D。
3. Instead of making choices for their children, liberal parents usually say, “Go where you ________ .”
A. will B. should
C. can D.must
【答案】A
【解析】考查情态动词。句意：开明的父母通常会说：“去你想去的地方吧”，而不是替他们的孩子做选择。A. will愿意，意志；B. should应该；C. can能够；D. must必须。故选A。
4. All the doctors in the hospital insisted that he ____ badly wounded and that he ____ at once.
A. should be; be operated on
B. were; must be operated on
C. be; was operated on
D. was; be operated on
【答案】D
【解析】考查insist的用法。句意为：医院里所有的医生都坚持认为他伤情很严重并坚决主张他必须马上做手术。Insist表示“坚持说、坚持认为”之意时，后面的从句使用陈述语气，表示“坚决主张、坚决要求” 之意时，后面的从句使用（should）do的虚拟语气。
5. — My sister is very upset today.
— It’s your fault. You ________ the bad news to her yesterday.
A. should tell B. should have told
C. shouldn’t have told D. must tell
【答案】C
【解析】考查情态动词+have done结构。句意为：——我妹妹今天很沮丧。——是你的错，你昨天不应该把那个坏消息告诉她。shouldn’t have done表示“不应该做而做了”。
6. —It’s just too difficult. I’ve tried several times but still cannot work it out.
—You _______a wrong approach. Adopt a new way and see what would happen.
A. should have taken B. needn’t have taken
C. must have taken D. can’t have taken
【答案】C
【解析】考查情态动词+have done结构。句意为：——它太难了。我尝试了很多次但还是没有算出来。——你一定是用错了方法，换一种新方法，然后看看怎么样。对过去的事情有把握的猜测用must have done。
7. Faced with the phenomenon that actors and actresses catch public attention, many people insisted that it _____
wrong and more _______ should be given to those devoted scientists.
A. was; credit B.be; honour
C. should be; appreciation D.is; recognition
【答案】A
【解析】考查insist的用法和名词辨析。句意为：面对男演员和女演员吸引公众注意的现象，很多人坚持认为这是不对的，人们应该赞许那些有献身精神的科学家。第一个空insist表示“坚持说、坚持认为”时，后面的从句不用虚拟语气，应该和insisted保持一致用一般过去时，第二个空give credit to表示“赞许”。
8. If you ______ the Minister of Education, which subject would you rather have _______ from the College
Entrance Examination?
A. are; included B. had been; been excluded
C. were to; include D. were; removed
【答案】D
【解析】考查虚拟语气和动词辨析。句意为：假如你是教育部长，你愿意把哪一科从大学入学考试中删除？第一个空表示对将来的假设，be动词应该用were的虚拟，第二个空remove…from…表示“把……从……中去掉”。
9. Judging from her expression, she the news that Charlie had returned from Britain.
A. shouldn’t have known B. can’t have known
C. mustn’t have known D. needn’t have known
【答案】B
【解析】考查情态动词+have done结构。句意为：从她的表情判断，她不可能知道Charlie已经从英国回来了。can’t have done表示“不可能做过”。
10. —Is Mike coming to this party?
—He should but he not. Because he has a lot of work to do tonight.
A. must B. need
C. may D. would
【答案】C
【解析】考查情态动词。句意为：——Mike将会来参加聚会吗？——应该会，但也可能不来，因为今晚他有很多作业要做。由句意可知用may表示“也许、可能”。
II. 语法填空
The distance between ancient Rome and ancient China was about 4,000 miles by land. It was a very 　1　(danger) trip with deserts and mountains. The Silk Road was a nickname for any route 　2　any trader took from China to Rome.
For a very long time, the ancient Romans did not know who was making the wonderful cloth 　3　(call) silk. They tried to find the traders as they came into villages to trade other goods for silk, but the traders 　4　(hide) from the Romans. Therefore, they had to trade for 　5　themselves. The trading along the Silk Road was a relay system. One trader would travel 　6　a while, stop and trade, and return home. The next trader would continue. And so it went. But 　7　(actual) no trader made the whole trip. It was too risky.
As the years went by, a civilization of sorts grew up along the Silk Road. Temples appeared. There were even 　8　(city) built on the rare oasis (绿洲). It was never easy　9　(travel) by land from China to Rome, but it was worth it. Romans traded gold for China’s silk and spices. But 　10　(many) things traveled the Silk Road than traders and goods. Ideas that changed the world traveled along the Silk Road as well.
II. 语法填空
【文章大意】本文是说明文，介绍了丝绸之路的起源。
1. dangerous 【解析】考查形容词。这是一段非常危险的旅程。修饰trip应用形容词，故填dangerous。
2. that 【解析】考查定语从句。丝绸之路是任何商人走的从中国到罗马的任何路线的别称。分析句子结构可知，空处在此引导定语从句，在从句中作took的宾语，且先行词route前有any修饰，故此处只能用关系代词that。
3. called 【解析】考查非谓语动词。很长时间以来，古罗马人不知道是谁生产出了这种被称为丝绸的极好的布料。cloth与call之间是逻辑上的动宾关系，故用过去分词作后置定语，填called。
4. hid 【解析】考查动词时态。但是那些商人躲开了罗马人。本文的基本时态为一般过去时，故此处亦用一般过去时。hide的过去式是hid。
5. it 【解析】考查代词。因此他们不得不自己(用其他物品来)换取丝绸。根据语境可知，空处指代上文中的"silk"，故填it。
6. for 【解析】考查介词。 一个商人会旅行一段时间，(然后)停下来进行交易，随后返回。for a while"暂时，一会儿"，是固定搭配。
7. actually 【解析】考查副词。但是，事实上没有一个商人成功地走完全程。分析句子结构可知，空处在句中作状语，修饰整个句子，故应用副词形式。actually"事实上，实际上"。
8. cities 【解析】考查名词复数。由句中的were可知这里要用名词复数，故填cities。
9. to travel 【解析】考查非谓语动词。走陆路从中国到罗马绝非易事，但很值得。此处考查的是"it is + adj. + to do sth."这一固定结构，it在这里作形式主语，真正的主语是后面的动词不定式，故填to travel。
10. more 【解析】考查形容词比较级。在丝绸之路上传送的事物比商人和货物更多。由句中的than可知这里要用形容词的比较级，故填more。
虚拟语气专项练习50题
1．--- I’m sorry. I _______ at you the other day.
--- Forget it. I was a bit out of control myself.
A. shouldn’t shout
B. shouldn’t have shouted
C. mustn’t shout
D. mustn’t have shouted
2 Thank you for all y our hard work last week. I don’t think we ____ it without you.
A. can manage
B. could have managed
C. could manage
D. can have managed
3. ____ he had not hurt his leg, John would have won the race.
A. If
B. Since
C. Though
D. When
4 --- If the traffic hadn’t been so heavy, I could have been back by 6 o’clock.
--- What a pity! Tina ____here to see you.
A. is
B. was
C. would be
D. has been
5 I was really anxious about you. You ____home without a word.
A. mustn’t leave
B. shouldn’t have left
C. couldn’t have left
D. needn’t leave
6 He suggested that the person ____to be punished.
A. refers
B. refer
C. should refer
D. referred
7 --- Do you think the thief entered the room through the back door?
--- No, if he had, I don’t believe he ____the living-room window.
A. would break
B. broke
C. would have broken
D. breaks
8 Without electricity, human life ____quite different today.
A. is
B. will be
C. would have been
D. would be
9 --- ____he come to see you as he promised?
--- Of course, please, and I’d rather he ____ me the truth.
A. Will; informed
B. Shall; told
C. Should; will tell
D. Can; tell
10 --- He looks very hot and dry.
--- So ____ if you had a temperature of 39.
A. would you
B. will you
C. would you have been
D. do you
11 I forget where I read the article, or I ________ it to you now.
A. will show
B. would show
C. am going to show
D. am showing
12. “It looks as if he were drunk.” “So it does. _________.”
A. He’d better give up drinking
B. He shouldn’t have drunk so much
C. Health is more important than drink
D. I wonder why he is always doing so
13. “Mary looks hot and dry” “So _________ you if you had so high a fever.”
A. do
B. are
C. will
D. would
14. “He will come tomorrow.” “But I’d rather he _________ the day after tomorrow.”
A. will come
B. is coming
C. came
D. had come
15. All the doctors in the hospital insisted that he ________ badly wounded and that he ________ at once.
A. should be; be operated on
B. were; must be operated on
C. was; should be operated
D. was; be operated on
16. _________ smoking, he would not have got cancer in the lung.
A. Was he given up
B. Had he given up
C. Did he give
D. If he gave up
17. What a pity! Considering his ability and experience, he ____ better。
A. need have done
B. must have done
C. can have done
D. might have done
18. I to go for a walk, but someone called and I couldn’t get way。
A. was planning
B. had planned
C. planned
D. would plan
19. I would like _______ you to my birthday party, but I was busy and forgot to call you。
A. to invite
B. inviting
C. to have invited
D. having invited
20. Had Paul received six more votes in the last election, he ______ our chairman now.
A. must have been
B. would have been
C. were
D. would be
21. ______ the English examination I would have gone to the concert last Sunday.
A. In spite of
B. But for
C. Because of
D. As for
22．The sun rises in the east and sets in the west, so it seems as if the sun ________round the earth.
A. were circling
B. circles
C. is circling
D. be circling
23．Had he worked harder, he _____ the exams.
A. must have got through
B. would have got through
C. would get through
D. could get through
24．I'd rather you _____ by train, because I can't bear the idea of your being in an airplane in such bad weather.
A. would go
B. should go
C. went
D. had gone
25．_____ for the timely investment from the general public, our company would not be so thriving as it is.
A. Had it not been
B. Were it not
C. Be it not
D. Should it not be
26. We are all for your proposal that discussion _____.
A. be put off
B. was put off
C. should put off
D. is to put off
27. Look at the terrible situation I am in! If only I ____ your advice.
A. follow
B. had followed
C. would follow
D. have followed
28. Without electronic computers, much of today’s advanced technology ______ .
A. will not have been achieved
B. have not been achieved
C. would not have been achieved
D. had not been achieved
29. When Edison died, it was proposed that the American people _______ all power in their homes, streets, and factories for several minutes in honour of this great man.
A. turn off
B. turned off
C. would turn off
D. had turned off
30. There is a real possibility that these animals could be frightened, _______a sudden loud noise.
A. being there
B. should there be
C. there was
D. there having been
31. Looking round the town, he felt as though he ______ away for ages.
A. has been
B. was
C. is
D. had been
32. Jean doesn't want to work right away because she thinks that if she ______ a job she probably wouldn't be able to see her friends very often.
A. has to get
B. had got
C. were to get
D. could have got
33.____ you known the truth, you should have told him .
A. Have
B. Had
C. Having
D. If
34. It’s high time you ______.
A. start to work
B. would start to work
C. started to work
D. had started to work
35. Bob would have helped us yesterday, but he-_______
A. was busy
B. is busy
C. had been busy.
D. will be busy
36. 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
37. 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
38. --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. hadn't died
D. wouldn't have died
39. Had I known about this computer program, a huge amount of time and energy______ .
A．would have been saved B．had been saved
C．will be saved D．was saved
40.---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
41. _____ the sun, nothing on earth could live.
A. Were it not to B. If it were not to
C. If it had not been for D. If it were not for
42. If he _____, give him the message.
A. were coming B. would come C. should come D. were come
43. Were I to move to a foreign country, I _____ away all my furniture in my house here.
A. would give B. shall give C. gave D. will give
44. I would go to the concert but I _____ no time.
A. had B. had had C. have D. has
45. —Would you have told him the answer?
—Yes, I would have, but I _____ so busy then.
A. had been B. were C. was D. am
46. —Why didn’t you buy it?
—I _____ but I didn’t have the money.
A. would B. would have C. had had D. had bought
47. —You should have finished it sooner.
—I know but I _____ the time.
A. don’t have B. won’t have C. didn’t have D. had not
48. _____ water, we could not live a day in the desert.
A. Without B. No C. Having no D. But not for
49. If you _____ the doctor’s advice, you would have recovered already.
A. followed B. would followed C. will follow D. had followed
50. If he had not lost the money, he _____ the piano last week.
A. could have bought B. had bought C. would buy D. have bought















参考答案与解析：
1. B。考查虚拟语气中情态动词的选择。should have done是虚拟用法，表示对过去情况的后悔或责备，D项语气太重，不符合语境。
2. B。此题考查情态动词表示虚拟意义的用法。I don’t think…是否定前移。意为：我认为没有你我们本不能做成这件事的。此题关键是要根据句意知道是虚拟语气，其基本形式是情态动词（过去式）+ have done，所以其他选项皆可排除。
3. A。从题干意思看，句子明显用虚拟语气。If可引导虚拟的条件从句，指与事实相反或不可能实现的假设。对过去的情景表达虚拟时条件句谓语用had + 过去分词，主句用would/ could/ should have done形式。
4. B。透过虚拟语气透漏的信息：因交通拥挤，我六点以前没能及时赶回；所以下文说：真遗憾，Tina六点以前在（was）这里（要见你，但现在已经走了），上句虚拟，下句真实。
5. B。语境告诉考生，说话者对对方非常担心又满怀关切之情，既着急又生气，因此难免说出埋怨的话：你本不该不辞而别（而使我如此担心）。shouldn’t have left是一种虚拟说法，即“过去本不该离开”，符合语境。
6. D。suggest的宾语从句常用虚拟语气“(should)+原形动词”，故易误选B, C.其实该题考查的是过去分词短语referred to作定语，从句的谓语是(should) be punished.
7. C。对话中的No是关键词，说明答话人已经否认小偷进入过房间，所以后面的议论用的是与过去事实相反的虚拟语气。
8. D。“假如今天没有电，人们的生活就大不同了”，是一种虚拟表达，要用与现在事实相反的虚拟语气谓语，故选D. 这里Without短语表示虚拟条件。
9. B。考查情态动词和虚拟语气的运用。表示征询意见，shall用于第一、三人称；would rather 后接从句用过去时表示虚拟语气。
10. A。根据句子的内在逻辑暗示这里应用“so +谓语+主语”句型表示前边的一种情况也适用于后者；本句中从句谓语动词had是解题的关键，这暗示if从句使用了虚拟语气，那么与将来事实相反的主句谓语要用could，would＋原形动词等，故选A。
11．B。几个干扰项均有可能误选。正确答案选B。根据上文的语境可知句中的or 隐含有一个虚拟的条件，即or=if I didn’t forget where I read the article（要是我没忘记我在哪儿读过这篇文章的话——但事实上忘了）。
12．D。几个干扰项均有可能误选，主要是受句中drunk 一词的影响。最佳答案为D。关键信息是It looks as if he were drunk 中的虚拟语气，句子既然用了虚拟语气，也就是说，“他喝醉了”不是事实，只是他的言行好像是醉了，所以此题的最佳答案是D。
13．D。容易误选A或C。选A者，认为前后两句的动词性质应一致；选C者，认为其后带有if 条件状语从句，从语气上看，主句应用将来时态。此题最佳答案为D。
14．C。容易误选A或B。根据上文的He will come tomorrow 以及下文的时间状语the day after tomorrow 似乎都表明空白处应填一个一般将来时态。但此题的最佳答案是C。按照英语习惯，would rather 后接that 从句时，从句谓语通常要用虚拟语气，即用过去式表示现在或将来，用过去完成时表示过去。
15．D。几个干扰项均有可能误选。最佳答案选D。insist后的从句谓语有时用“should+动词原形”这样的虚拟语气，有时不用，具体要看该谓语动词所表示的含义。一般说来，若该谓
语动词所表示的动作尚未发生，或尚未成为事实，则用虚拟语气；若该谓语动词所表示的动作已经发生，或已经成为事实，则要用陈述语气。分析上题的句意，可知只有选D最合适。16．B。容易误选D。正确答案应选B。之所以不能选D，是因为时态前后有矛盾。由于主句谓语是would not have got，这表明是对过去事实作出的假设，所以从句谓语应该是had given up，而不是像D项那样用一般过去时。另外，当虚拟条件句中有had, should, were 等词时，通常可以省略if，并将had, should, were 提前置于句首。
17．D。 “What a pity!”暗示他的表现令人遗憾。鉴于他的能力和经验，他本来可能发挥得更好，因此用might have done，最佳答案为D。
18．B。 句意为：我原计划去散步，但是有人来访，我无法走开。had planned to do sth表示过去未能实现的打算。最佳答案为B。
19．C。 句意为：我本来想让你参加我的生日宴会，可是因为忙，我忘记了。would like to have done sth。表示“本来想做某事(而未做)”。最佳答案为C。
20．D。 这道题目是一个混合虚拟语气的句子。条件句省略了if，把助词had提前到主语前面，表示对过去情况的假设，而主句中now表明了对现在情况的假设，所以应选would(should, could, might)+动词原形这种表达形式。四个选项中只有（D）是正确表达形式，故为正确答案。
21．B。 假设的情况有时不是用一个条件句表示，而是隐含在一个由介词如but for、but that、without, 由连词but、副词otherwise 、比较级、形容词、独立主格等表示的上下文中。本句主句表示对过去情况的假设，但事实上由于英语考试而没有去成，即若不是因为英语考试，我本可以去听音乐会，所以应选（B）But for为正确答案。
22．A。 if引导的从句要求用虚拟语气，表示同时或将来的情况，动词要用过去式（be 动词用were）或would(could等)+动词原形，本句话中指的是当时的情况，所以要用过去式，故（A）是正确答案。
23．B。 本题前半句是表示与过去事实相反的虚拟条件从句，后半句是表示与过去事实相反的主句。相当于：If he had worked harder, he would have got through the exams.本题的答案是B. would have got through。选项A. must have got through（肯定通过）表示一种对过去事情的主观推测，不是与过去事情相反的情况。另外，must不能用在虚拟条件句中。选项C. would get through（就会通过）是虚拟语气现在时的一种表示方法，表示与现在事实相反。选项D. could get through（可能通过），could也可以用于非真实条件句里，表示与事实相反的情况，但这里，它只表示与现在事实或将来可能的事实相反。
24．C。 主语+would rather后接宾语从句,从句中谓语须用虚拟语气：用一般过去时表示希望现在或将来实现的行为或状态,用过去完成时表示希望过去实现的行为或状态。本题中原因状语从句用一般现在时,暗示希望现在或将来发生的行为动作,故选C. went。25．A． “要不是老百姓的及时投资，我们的公司不会像现在这样兴旺。”本题测试交错时间的虚拟语气。从句是表示过去时间的虚拟条件，if省略，主语it与助动词had倒装。虚拟条件句也可写成这样：If it had nor been for the timely investment from the general public。这是重点句型，在各类测试中常考。
26. A. 全句意思是：我们都赞成你的建议，把讨论推迟。答案是A。
27. B。 if only 引出感叹句，意思是“要是……多好”，表示说话人的一种愿望，希望发生（事实上不可能发生）与过去事实相反的情况。本句的全句意思是：“看我现在的处境多糟糕！要是我听从你的劝告多好”。事实上，句中的“我”没有听从劝告，所以处境很糟糕。
28. C. 这是一人含蓄虚拟条件句，通过介词短语without,表示潜在的一种假设，而主句中的情况也早已经发生，所以是对过去情况的一种假设，因此用would not have been achieved 这一形式。
29. A propose是欲望动词,后接的宾语从句或主语从句中谓语要用虚拟语气：should+动词原形或直接用动词原形。
30. B。 句意为：“要是有一声巨响，这些动物会受到惊吓，这是有现实可能性的。”should there be表示虚拟条件句中将来时间的谓语形式, if省略,所以should与there倒装。因此B. should there be 就是本题答案。
31. D。 felt是过去式，所以该句是由as though引导的与过去相反的虚拟。
32. C。 本句的意思是：“琼不想马上就工作，她认为要是找了工作，就不能经常探访她的朋友了”。这说明，琼目前没有工作。句中假设的情况在近期内并不会存在。该条件句应当用表示将来情况的虚拟语气。条件从句的谓语用should或were to引出。因此C. were to get 是本题答案。33.B.解析:句子可还原为If you had known the truth, you should have told him . If+ had done,主句为could/ should/ would have done.
34. C. 考查句型It’s high time后接虚拟语气用法。
35. A. 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。
36. D. 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。 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。
37. B. 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。
38. D。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.
39. A。 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。
40. C。 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。
41. D。表示与现在事实相反的虚拟语气，意思是“如果不是有太阳的话”。
42. C。表示与将来事实相反的虚拟语气，从句用should do.
43. A。表示与将来事实相反的虚拟语气，主句用would/should do.
44. C。 but后面的分句表示事实情况，不用虚拟语气。
45. C。 but后面的分句表示过去的事实情况，因此用过去时。
46. B。虚拟语气和事实情况混合的用法，第一个分句是虚拟，而but后面是事实情况。
47. C。 but后面的分句表示过去的事实情况，因此用过去时。
48. A。 without经常代替虚拟的从句，表示假设。
49. D。 表示与过去事实相反的虚拟语气，从句用过去完成时。
50. A 。could have done表示“本来可以做某事”。