Unit13虚拟语气专题讲解【知识要点】语气（mood）是一种动词形式，用以表示说话者的意图或态度。
英语有三种语气：＊直陈语气（indicative mood）---- 事实France lies to the east of England.＊祈使语气（imperative mood）---- 请求、命令Make yourself at home.＊虚拟语气（subjunctive mood）If there were no air and water , we should not be able to live on the earth.虚拟语气表示说话人的一种主观愿望或假想，所说的是一个条件而不一定是事实，或与事实相反。
一. 虚拟语气在if条件状语从句中的用法假设类型条件从句谓语动词形式主语谓语动词形式与现在事实相反动词的过去式(be用were而不用was) should/ would /could/ might+动词原形与过去事实相反had + 过去分词should/ would/could /might + have+过去分词与将来事实相反1.should+动词原形2.动词过去式3.were to+动词原形should/ would/ could/ might +动词原形1. 在错综条件句子中，虚拟条件从句和主句动作发生的时间不一致，因此，主句和从句的谓语动词应根据所指的时间选用适当的虚拟语气形式。
1）If I were you，I wouldn't have missed the film last night．2）If he had followed the doctor's advice，he would recover already．（从句与过去事实相反，主句与现在事实相反。
）2、在if虚拟条件句中，有时可把连词省去，采用倒装语序把谓语动词were或助动词did，had，should 移到句首构成非真实条件从句的另一种句型，其意思不变。
1）Had we time to spare，we would be glad to go to the park．2）Were it not for the discovery of electricity，the modern world would experience great inconvenience．3、有时假设的情况不用if引导虚拟条件从句来表述，而用介词（如without， but for等）引出的短语、分词（如supposing等）引出的短语、并列连词（如or，otherwise，but，though等）、由动词suppose引出的祈使句或通过上下文的意思来表达。
此时句中谓语动词仍采用虚拟语气的相应形式。
1）But for your advice，I would not be able to do this work．2）Victor obviously doesn't know what's happened，otherwise he wouldn't have made such a stupid remark．。
4、通过Were it not for...或Had it not been for...等句式表达条件Were it not for(=If it were not for) the leadership of the Party,we could not live a happy life.Given more attention, the trees could have grown better.与现在事实相反过去时（were）与过去事实相反had+过去分词与将来事实相反would/could/might+动词原形I wish I were as tall as you.He wished he hadn't said that.I wish it would rain tomorrow.三．表示要求,命令,建议的虚拟语气一个（坚持） ___insist______两个（命令） ___order, command_________三个（建议） ___suggest, advise, propose_(recommend)__四个（要求） __require, demand, request, __ask________这些动词后面的宾语从句要使用虚拟语气用法。
即从句中的动词使用should + 动词原形, 或者将should省略。
The doctor suggested that he (should) try to lose his weight.He insisted that we (should) tell him the news.It is arranged that he leave for Canada on Friday.What do you think of his proposal that we should put on a play at the English eveningMy suggestion is that we should go there at once.四．It’s necessary/strange/natural/ important/pity/no wonder/impossible + that Clause 从句中的动词要用虚拟, 即(should)+动词原形I It is a great pity that you (should) think so.It is highly desirable that a new president be appointed for this college．It is strange that the girl（should）be so arrogant．五. would rather 后的宾语从句,用虚拟语气I would rather you could teach me again.The manager would rather that his secretary went to the meeting instead of him .六. as if， as though引导的从句, 用虚拟语气以as if 、as though（似乎，仿佛）引出的方式状语从，如果表示真实情况应该用直陈语气；如果表示非真实情况，都必须用虚拟语气。
当从句表示与现在的事实相反，谓语动词用一般过去时；表示与过去事实相反要用"had ＋过去分词"；表示与将来可能相反的则用"would（could，might）＋动词原形"。
The little boy knows so many things as if he were an adultHe acted as usual as though nothing had happened.七. 由if only （要是……，那该多好啊！）引导的惊叹句,用虚拟语气If only I had passed the test ！If only it stopped raining！If only I had taken mother's advice比较if only与only ifonly if表示“只有"；if only则表示"如果……就好了"。
If only也可用于陈述语气。
I wake up only if the alarm clock rings. 只有闹钟响了，我才会醒。
If only the alarm clock had rung. 当时闹钟响了，就好了。
If only he comes early. 但愿他早点回来。
八. It is (high) time thatIt is (high) time that 后面的从句谓语动词要用过去式或用should加动词原形，但should不可省略。
It is time that the children went to bed.It is high time that the children should go to bed.It is high time that we had our lunch. 该是我们吃午饭的时候了。
It is time that he made up his mind. 该是他作出决定的时候了。
九、在和idea，necessity，plan， motion，order，proposal，recommendation，suggestion，under- standing 等词有关的同位语或表语从句中，谓语动词用动词原形或"should ＋动词原形"表示虚拟语气。
My idea is that the group（should）hold another session to discuss the problem．Emphasis is laid on the necessity that all the objectives to be attained be taken into account before starting a new project．十、虚拟语气用在简单句中，表示祝愿，命令。
May you be happy. 祝你幸福。
May you have a good time. 祝愿你玩的痛快十一、情态动词中的虚拟语气didn't need to do表示：过去不必做某事, 事实上也没做。
.needn't have done表示：过去不必做某事, 但事实上做了。
John went to the station with the car to meet Mary, so she didn't need to walk back home. 约翰开车去车站接玛丽，所以她不必步行回家了。
John went to the station with the car to meet Mary, so she needn't have walked back home. 约翰开车去车站接玛丽，所以她本不必步行回家了。
(Mary步行回家，没有遇上John的车。
)You shouldn’t come here yesterday.I should have worked hard last year, but I didn’t.基础练习：1. We demanded that we __________ of any change in the plan.A． informed B. would be informed C. be informed D. had been informed2. It’s necessary that he _________ a recognized qualification.A. hasB. haveC. hadD. having3. It's high time we ____________ our attention to this problem.A. turnedB. turnC. had turnedD. would turn4. If only you __________ him what I said! Everything would have been all right.A. didn't toldB. hadn't toldC. would not tellD. would have not told5. He must have had an accident, or he____________ here then.A. would have beenB. had beenC. should have beenD. could be6. Much labour would have been saved if the electronic computers_____________ before.A. had inventedB. were inventedC. should have been inventedD. had been invented7. _____________ cease advertising, prices would be significantly reduced.A. Were they toB. Could theyC. If theyD. Would they8. Five minutes earlier, and we ____________ the last bus.A. had caughtB. should have caughtC. could have caughtD. caught9. You ____________ the clothes! We have a washerwoman to do that sort of thing.A. shouldn't have washedB. mustn't have washedC. can not have washedD. needn't have washed10. 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 getB. were to getC. had gotD. could have got11. The mad man was put in the soft-padded cell lest he _____________ himself.A. injureB. had injuredC. injuredD. would injure12. It is politely requested by the hotel management that radios __________ after 11 o'clock at night.A. were not playedB. not to playC. not be playedD. did not play13. You don't have to be in such a hurry. I would rather you _________ on business first.A. would goB. will goC.went D. have gone14. It is important that enough money ___________ to fund the project.A. be collectedB. must be collectedC. was collectedD. can be collected15. If only the committee __________ the regulations and put them into effect as soon as possible.A. approveB. will approveC. can approveD. would approve16. I don't think it advisable that Tom ________ to the job since he has no experience.A. is assignedB. will be assignedC. be assignedD. has been assigned17. You _________ her in her office last Friday; she's been out of town for two weeks.A. needn't have seenB. must have seenC. might have seenD. can't have seen18. We didn't know his telephone number, otherwise we _________ him.A. would have telephonedB. must have telephonedC. would telephoneD. had telephoned19. It is recommended that the project _________ until all the preparations have been made.A. is not startedB. will not be startedC. not be startedD. is not to be started20. I wish I ________ longer this morning, but I had to get up and come to class.A. could have sleptB. sleptC. might have sleptD. have slept提高练习1. If I _________ the opportunity I would not have missed it.A. had givenB. was givenC. had been givingD. had been given2. If we _______ yesterday, we _________ the work.A. weren't interrupted.., would finishB. didn't interrupt.., would have finishedC. hadn't been interrupted., would have finishedD. hadn't interrupted.., would have finished3. If the transfer of power in Iraq had taken place later than June 28，2004, more attacks from Iraqi _______ to American soldiers.A. would have happenedB. would happenC. will have happenedD. could have happened4. Your examination results were quite satisfactory, but ________ if you had spent less time in playing football?A. wouldn't they have been betterB. wouldn't they bebetterC. won't they be betterD.won't they have been better5. I didn't know this Picasso exhibit was closed, but I wouldn't have been able to come even if _________ about it.A. I knowB. I'd knownC. I have been knowingD. I've known6. If he ___________ hard in the past five years, things wouldn't be going so smoothly.A. had not been workingB. has not been workingC. was not workingD. were not working7. Do you think the thief entered through the garage door?No. If he had, I don't believe he __________ the living room window.A. would have brokenB. had brokenC. has brokenD. broke8. With all this work on hand, he __________ to the cinema last night.A. mustn't goB. wouldn't goC. oughtn't to goD. shouldn't have gone9. I'd rather you __________ anything about it for the time being.A. doB. didn't doC. don't doD. didn't10. One of the requirements for a fire is that the material _____ to its burning temperature.A. be heatedB. is heatedC. would be heatedD. to heat11. He is working hard for fear that he ___________ .A. fell behindB. may fall behindC. should fall behindD. would fall behind12. _____ to do the work, I should do it some other day.A. If were IB. I wereC. Were ID. Was I13. It is highly desirable that a new chairman ___________ for the committee.A. will be electedB. is electedC. electD. be elected14. It is requested that every student ___________ a plan for the next semester.A. makesB. makeC. will makeD. would make15. The librarian recommended that the professor __________ the newly published book.A. borrowB.borrowedC. should have borrowedD. borrowing16. If they _________ the contract ahead of time, they could not have missed the plan.A. signedB. had signedC.would have signedD. should sign17. I don't think it advisable that he _________ to the job since he has no experience.A. be assignedB. wi ll be assignedC. is assignedD. has been assigned18. What do you think of his proposal that we __________ put on a play at the English evening?A. willB. shouldC. hasD. have19. He must have missed the train, otherwise he _________ then.A. should arrive hereB. has arrived hereC. would have arrived hereD. arrived here20. It ___________ a mistake not to help him.A. will heB.can heC. would beD. is21. Mr. Johnson prefers that _________ with him personally.A. she speaksB. she will speakC. she speakD. she would speak22. You _________ yesterday, if you were really serious about the job.A. ought to come C. ought to be comingB. ought to have come D. ought have come23. The old worker urged that we __________ cheaper materials instead.A. useB. usedC. would useD. will use24. When he took the pen back to Mary, she said coldly, You ______ it sooner, for I ________ it.A. should have returned.., might needB. should have returned.., might have neededC. should return.., might have neededD. must have returned.., must have needed25. I would have written before, but I __________ ill then.A. amB. wasC. had beenD. would be26. Suppose/Supposing you _________ him now, what would you say to him?A. meetB. metC. have metD. would meet27. Susan _____ written a report like this.A. can haveB. mustn’t haveC. can’t haveD. ought to not have28. You ________ to town to see the film last week. It will be on TV tomorrow.A. needn't goB. should not goC. had better not goD. needn't have gone29. I ________ her to the party but I didn't know her well.A. ought have invitedB. would have invitedC. should inviteD. may have invited30. Helen doesn't know how much I spent in repairing the house; if she ever found out, I'm sure she __________ me.A. would never forgive C. does never forgiveB. never forgives D. will never forgive强化题1. — The Chinese athletes did extremely well in the Athens Olympics.— Yes， they _______ very hard, or they such great achievement.A. must have been trained；couldn’t have gotB. must have trained； could have gotC. must have been trained；mustn’t have gotD. should have been trained；couldn’t have got2. Everything _______ if Albert hadn’t called the fire brigade ( 消防队).A. will be destroyedB. will have been destroyedC. would be destroyedD. would have been destroyed3. We ______ last night， but we went to the concert instead.A. must have studiedB. might studyC. should have studiedD. would study4. — If he _______ ， he _______ that food.— Luckily he was sent to the hospital immediately.A. was warned； would not takeB. had been warned； would not have takenC. would be warned； had not takenD. would have been warned； had not taken5. — But for the bird flu ( 禽流感 ) in Vietnam in the summer of 2004，I ______ you to go to Vietnam for sightseeing.— Really？ What a pity！A. have takenB. had takenC. should have takenD. would have taken6. Without the air to hold some of the sun’s heat， the earth at night ______ ， too cold for us to live.A. would be freezing coldB. will be freezing coldlyC. would be frozen coldD. can freeze coldly7. He told me how he had given me shelter and protection without which I ______ of hunger and cold.A. would be diedB. would have diedC. would dieD. will have died8. I should very much like to have gone to the party but I _______.A. am not invitedB. was not invitedC. shall not be invitedD. am not being invited9. — Some American and British soldiers abused (虐待) the war prisoners in Iraq.—I think it’s necessary that they ______ seriously according to the international law.A. punishB. be punishedC. must be punishedD. will be punished10. What do you think of his proposal that improvements ______ in the old type of heater？A. be madeB. will be madeC. would be madeD. will have to be made11. — Did you go to see the football match yesterday？—No. I didn’t feel well, but I would have gone if I ______ .A. didB. haveC. wouldD. had12. ______ ， we could not have finished the work on time.A. If they do not help usB. Was it not for their helpC. Should they offer to help usD. But for their help13. If we had been more careful， we _______ much better results now.A. gotB. had gotC. would be gettingD. would have got14. Henry _______ a rich man today if he had been more diligent in the past.A. would beB. isC. will beD. was15. They thought it desirable that an armed guard______ in readiness.A. standsB. standC. stoodD. would stand参考答案：基础题1—5 CBABA 6-10 DACAB 11-15 CCCAD 16-20 CDACA提高题1—5 DCAAB 6—11 ABDBA 11—15 DCDBA16—20DABCC 21—25 DBABB 26—30 BCDDA强化题1-5 ADCBD 6-10 ABBBA 11-15 DDCAB。