1、【专题七】情态动词与虚拟语气【考情分析】1准确把握情态动词表允许、推测、判断等用法。2准确把握情态动词在虚拟语气句子结构中的使用。3wish，as if/though，if only，would rather从句，Its time从句等句型中的虚拟语气。4表示“坚持、命令、建议、要求”的词语后及各类从句中的虚拟语气。5虚拟语气在条件状语从句中的倒装。【知识归纳】情态动词考点一 情态动词的基本用法1can 和could的用法(1)表示惊讶，常用在否定句和疑问句中。How could you do such a silly thing?你怎么能做那样的蠢事呢？(2)cannot.too/enoug
2、h表示“无论也不过分”；“越越好”。You cant be too careful while driving.开车时越小心越好。2may和might的用法(1)may和might表示“许可”，“可能性”，“祝愿”等意义。在给予别人许可时，常用can，但有时也用may。不能用might。May I play basketball this afternoon?“今天下午我可以打篮球吗？”No，you may not.“不，不行。” “may as well动词原形”意为“最好，满可以，倒不如”。You may as well do it at once.你最好马上就做这件事。We may as
3、 well stay where we are.我们留在现在的地方倒也不错。(2)may作“可以”讲时，其否定式常用“mustnt”表示“禁止”；must作“必须”讲时，其否定式是“neednt”，表示“不必”。May I use your car?No，you mustnt.(委婉的拒绝可用：Sorry，but I am using it now.或Youd better not.等)Must I work out the problem tonight?No，you neednt.3must(1)表示禁止(用于否定句)You must not speak ill of others.你一定
4、不要说别人的坏话。Smoking must not be allowed in the office.严禁在办公室吸烟。(2)表示“偏执”，“固执”Must you make so much noise?你非得弄出这么大声吗？If you must smoke，please go out.如果你偏要吸烟，那你就出去吧。4shall的用法(1)用于第一、第三人称疑问句中，表示说话人征求对方的意见和向对方请示。Shall we begin our class?我们可以开始上课吗？Shall the driver wait outside?司机在外边等着可以吗？(2)用于第二、第三人称陈述句中，表示
5、说话人给对方的命令、警告、允诺或威胁。I promised he shall get a present for his birthday.我许诺给他一件生日礼物。You shall not get my support if you do such a thing.假如你做那种事，我就不支持你。5will和would的用法作情态动词的will，would与作助动词的will，would的各种形式相同。(1)表示自愿做或主动提出做什么，如意志、愿望或决心等。would用于过去的情况。John promised his doctor he would not smoke，and he has n
6、ever smoked ever since.约翰答应他的医生不再吸烟了，自从那时起他就再也不吸烟了。I have told him again and again to stop smoking，but he will not listen.我已再三告诉他戒烟，但是他就是不听。(2)will可以表示一种习惯性的动作，有“总是”或“总要”之意。Every morning he will have a walk along this river.每天早晨，他总是沿着小河散步。(3)would 可以表示过去的习惯性动作，比used to正式，但没有“现已无此习惯”的含义。Last year our
7、 English teacher would sometimes tell us stories in English after class.去年我们的英语老师常常课后给我们讲英语故事。考点二 情态动词的“推测”用法表示对目前或将来情况的推测往往用“情态动词动词原形”这种结构。1can用于肯定句中有时可以用来表示推测，意为“有时会”；用于疑问句中可以表示推测，意为“可能”，有时表示一种惊讶的语气；用于否定句中也可以表示推测，cant 意为“不可能”，语气很强烈。Mr.Bush is on time for everything.How can it be that he was late f
8、or the meeting?布什先生做什么事情都很准时，他怎么可能开会迟到呢？The story cant be true.这个故事不可能是真的。2may用于肯定句中可以用来表示推测，意为“可能”；用于否定句中也可以表示推测，may not意为“可能不”，表示一种不太确定的语气。may在疑问句中不能表示推测。Peter may come with us tonight，but he isnt sure yet.彼得今晚可能和我们一起来，但他还没确定。3must 表示推测时只能用于肯定句中，意为“一定，必定”，表示十分肯定的语气(在疑问句中或否定句中要用can)。He must be ill.
9、He looks so pale.他准是病了，他的脸色苍白。Its the office！So you must know eating is not allowed here.“这是办公室！所以你一定知道这里不许吃东西。”Oh，sorry.“噢，对不起。”4should 用来表示推测时意为“应该”，即含有“按道理来说应当如此”的意思。There shouldnt be any difficulty about passing the road test since you have practiced a lot in the driving school.因为你在驾校训练了那么多，通过路考
10、应该没什么困难。5表示对现在正在发生的事情进行推测要用“情态动词be现在分词”这种结构。这种结构在高考题中出现的次数不太多，但也提醒考生注意。My mother must be watering the flowers in the garden now.现在我母亲一定正在花园里浇花。The students may be climbing the mountain at the moment.此刻学生们有可能正在爬山。考点三 情态动词+have+过去分词用法表示对过去发生的情况或存在的状态的推测常用“情态动词have过去分词”这种结构。1can/could have done表示“本来可以做
11、，而实际上未做”或者“过去可能”，疑问或否定形式表示对过去发生的行为表示怀疑或不肯定，其中cant have done多用于语气强烈的否定，意为“不可能做过”。Do you know where David is？I couldnt find him anywhere.“你知道大卫在哪里吗？我到处找不到他。 Well.He cant have gone farhis coats still here.“大卫的上衣还在这里，因此他肯定没走远。”The accident could have been avoided.这场事故本来是可以避免的。2may/might have done表示对过去行为
12、的推测，意为“可能做过”。might所表示的可能性比较弱，语气较委婉。此外might have done可表示“本可能做而实际上未做”。Sorry，Im late.I might have turned off the alarm clock and gone back to sleep again.对不起，我迟到了。我可能把闹钟关掉后又睡着了。3must have done表示对过去行为的推测，意为“一定，想必”，语气十分肯定。He must have completed his work；otherwise，he wouldnt be enjoying himself by the sea
13、side.他一定是已经完成工作了，否则他不会在海边玩得那么高兴了。4ought to/should have done表示过去本来应该做某事而实际上却没有做；shouldnt have done表示过去本来不应该做某事而实际上却做了。这一用法往往含有责备的意味。Im not feeling well in the stomach.I shouldnt have eaten so much fried chicken just now.我现在觉得肚子疼，我刚才真不应该吃那么多的炸鸡的。5neednt have done表示本来不必做某事而实际上却做了。Catherine，I have clean
14、ed the room for you.“Catherine，我已替你打扫了房间。”Thanks.You neednt have done it.I could manage it myself.“谢谢。你本来不必做，我自己可以做的。”虚拟语气1在非真实条件句中谓语动词用虚拟语气非真实条件句有以下三类：(1)与现在事实相反的非真实条件句，谓语动词形式如下：从句：过去式主句：would/should/could/might动词原形。(2)与过去事实相反的非真实条件句，谓语动词形式如下：从句：过去完成时主句：would/should/could/might have过去分词。 (3)与将来事实相反
15、的非真实条件句，谓语动词形式如下：从句：过去式/should动词原形/were to动词原形。主句：would/should/could/might动词原形。【专家提醒】(1)若条件句中有were，had，should，可把if省略，而把were，had，should放在主语前，形成倒装结构，这种结构主要用于书面语中。Had you taken my advice，you wouldnt have failed in the examination.如果你听了我的建议，你就不会考试不及格了。(2)有时主句和虚拟条件从句的动作发生的时间不一致，此时，主句和从句的谓语动词要根据各自所指的不同时间选
16、择适当的动词形式。If you had worked hard，you would be very tired now.如果你真的努力工作了，你现在就会感到很累的。(从句指过去，主句指现在)(3)有时虚拟条件并不通过条件从句表达出来，而是通过词、短语或上下文暗示，此时句子的时态要依具体情况而定。Without electricity(If there were no electricity)，life would be quite different today. 如果没有电，今天的生活就会完全不同。But for your help(If it hadnt been for your hel
17、p)，I couldnt have finished it.要是没有你的帮助，我就不可能完成这件事。I was busy that day. Otherwise I would have gone there with them.(If I hadnt been busy that day，I would have gone there with them.)我那天很忙，否则，我就和他们一起去那儿了。2虚拟语气在某些从句中的应用(1)用在suggest，order，demand，ask，command，propose，request，insist等动词后面的宾语从句中。(2)用在wish后面的
18、宾语从句中。(3)用在以as if/as though引起的从句中。(4)用在以in order that，so that引起的目的状语从句中。(5)用在以it is(high)time引起的从句中。(6)用在混合时间条件句中：主句和从句不一定用指同一时间的动词。如：If I had learned French，I would be able to interpret for our French friends.如果我以前学过法语，现在我就能给法国朋友当翻译了。(7) would rather句型中的虚拟语气表示愿望，意为“宁愿，但愿”。如：Id rather we didnt go to
19、 see a film this evening.我倒希望我们今晚不去看电影。(8)无主句条件句。如：If only I had been more careful!我要是再仔细一点就好了！【考点例析】1.We _have bought so much food now that Suzie wont be with us for dinner. 【2012江西卷】Amay notBneedntCcantDmustnt 1.B考查情态动词的用法。句意为：既然Suzie不和我们一起吃晚饭，所以我们就不需要买这么多食物。may not不可以，neednt不需要，cant不可能， mustnt绝不可
20、能。故B为正确答案。2.Sorry, I am too busy now. If I _ time, I would certainly go for an outing with you. 2012湖南卷A. have hadB. had hadC. haveD. had2. D 此题考查条件状语从句中的虚拟语气，从句中用一般过去时表现在的假设。根据句意，试题应为对现在情况的虚拟，故正确答案为D。 3.-_you interrupt now? Cant you see Im on the phone? 【2012重庆卷】 -Sorry Sir, but its urgent. A. Can
21、B. Should C. Must D. Would3. C 考查情态动词用法。句意：“你现在一定要打断我吗？难道你不能看到我在打电话吗？对不起，先生，事情很急。”根据语境结合选项的词义，C选项符合题意。因此，正确答案为C选项。4. One of our rules is that every student wear school uniform while at school. 【2012辽宁卷】A. might B. could C. shall D. will4. C 本题考查情态动词。Shall用于第二、第三人称，表示说话人给对方命令、警告、允诺或威胁。这儿是说根据学校规定学生在校时
22、都必须要穿校服。故正确答案为C。5. I got close enough to hear them speaking Chinese, and I said “Ni Hao ” just as I _ do in China. 【2012四川卷】A. must B. might C. can D. should 5.B 本题考查情态动词。句意为：我靠他们足够的近以听见他们说汉语，而且我会像我在中国可能做的那样说“你好”。might表示“可能”。故选B。6. If my car _more reliable, I would have driven to Lhasa instead of fl
23、ying last summer. 【2012陕西卷】A. was B. had beenC. should be D. would be6.B 考查虚拟语气。根据主语的谓语动词可知题干是表示与过去事实相反的虚拟语气，从句谓语动词用had done，选B。7.I_ thank you too much for all your help to my son while we were away from home. 【2012陕西卷】 A. wont B. cant C. can D. will 7.B 考查情态动词。所填情态动词与too 构成固定句型cant/couldnt too，意思是：
24、再都不为过，选B。8. I _use a clock to wake me up because at six oclock each morning the train comes by my house. 【2012全国新课程】A. couldnt B. mustnt C. shouldnt D. neednt8. D 考查情态动词的用法。句意：我没有必要用闹钟唤醒我，因为每天早上6点火车都经过我的房子。此处考查情态动词，neednt+动词原形表示：没有必要做某事。9. If we _adequate preparations, the conference wouldnt have be
25、en so successful. 【2012山东卷】A. havent madeB. wouldnt make C. didnt make D. hadnt made9. D考查虚拟语气的用法。句意：如果我们没有做好充分的准备，会议就不会这样成功。在虚拟条件句中，表示与过去事实相反的情况，从句用过去完成时，主句用would have done的形式。故D为正确答案。10. We lost our way in that small village, otherwise we_more places of interest yesterday. 【2012福建卷】A. visitedB. ha
26、d visitedC. would visit D. would have visited10. D本题考查虚拟语气的用法。本题关键是从时间状语yesterday知道是对过去的虚拟，前半句是个过去的客观事实“我们在那个小山村迷路”，otherwise否则后半句是用对过去的虚拟would have done，答案为D项。【方法技巧】1.情态动词表“推测和可能性、必要性、请求、允许、允诺”等有关知识应引起足够重视。 2.熟记并掌握虚拟语气在非真实条件句中的使用规则, 特别是主从句的具体形式应熟练掌握。3.熟练掌握虚拟语气在名词性从句中的使用。表语从句，同位语从句和主语从句中，表示间接的命令、要求、
27、请求、建议、决定等，主句的主语通常是suggestion, proposal, request, order, idea 等。 从句中的谓语动词是should +动词原型，should 可以省略4. 掌握一些特殊句型中要运用虚拟语气的具体规则。混合时间的虚拟语气，如果条件句中的动作和主句的动作不是同时发生，主句和从句的谓语动词的形式应分别根据各自所表示的时间加以调整。虚拟语气中的倒装句，如果虚拟语气的条件从句谓语动词中含有were, had, should，有时可将if省去，而将条件从句的主语置于were, had, should, 之后含蓄条件句，有时为了表达的需要，在虚拟语气中不总是出现i
28、f引导的条件句，而通过用其他词来代替条件句，常见词有otherwise, or, but for 和if only等【专题训练】1. Not every prisoner can travel，and we have strict and fair regulations. Those selected _have performed well in the prison and are going to be released soon.A. couldB. might C. must D. should2 I am going to buy the overcoat if the shop
29、 owner _lower the price.Amust Bshould Ccould Dwill3. According to the school rules, no student_go out of the school after eleven oclock.Awill Bmust Cmay Dshall4.Im leaving now.Its so late. Better stay with me. Call a taxi if you_.Awill Bmust C. would Dmay5.What do you mean by this?No need for you to
30、 worry about your money and be angry with me. You _get it this afternoon.A. will B. shall C. may D. need6. You _get the book on condition that you give it back to me in time.Ashould Bmust Cought to Dshall7 According to the school rules, no student_go out of school without the permission of the teach
31、ers.Awill Bmust Cmay Dshall8.It was the drug，not the disease，that killed the boy.He would be still alive today if he _that drug.A. not take B. shouldnt have takenC. didnt take D. hadnt taken9. Its a very kind offer, but I really _accept it. A. mustnt B. neednt C. cant D. dont10. I saw your uncle tak
32、e a taxi to the airport.Why didnt you drive him there.I._ But my car_.A. would；was fixed B. would have；was fixed C. would have；was being fixedD. did；was being fixed11. You_practise the drums while the baby is sleeping. A. neednt B. mightnt C. mustnt D. wont12. You_him the news; he knew it already. A
33、. neednt tell B. neednt have told C. mightnt tell D. mightnt have told13. “Isnt it about time you _to do morning exercises？” “Yes, it is. Would you like to join us？”A. begin B. have begun C. began D. had begun14. It is hard for me to imagine what I would be doing today if I_in love, at the age of se
34、ven, with the Melinda Cox Library in my hometown. A. wouldnt have fallen B. had not fallen C. should fall D. were to fall15. He hesitated for a moment before kicking the ball, otherwise he_a goal.A. had scored B. scored C. would score D. would have scored16. But for the help you gave me, I _ the exa
35、minations.A. would have passed B. would pass C. wouldnt have passed D. wouldnt pass17. I forget where I read the article, or I _ it to you now. A. will showB. would show C. am going to showD. am showing18. “Mary looks hot and dry” “So _ you if you had so high a fever.”A. do B. are C. will D. would19
36、. “He will come tomorrow.” “But Id rather he _ the day after tomorrow.”A. will come B. is coming C. came D. had come20. 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 onC. was; should be operated D. was; be operated on 【参考答案】1-5 CDDBB 6-10 DDDCC 11-15 CBCBD 16-20 CBDCD版权所有：高考资源网()版权所有：高考资源网()