爱华网 （一） 表示与现在、过去、将来事实相反的假设
1． 与现在事实相反的假设。
其句子结构为：
从句：if+主语+动词的过去式（be变were）+其他
主句：主语+would(should, could, might)+动词原形+其他
例：If I were you, I would go with him.
2． 与过去事实相反的假设。
其句子结构为：
从句：If+主语+过去完成时+其他
主句：主语+should(would, could, might)+现在完成时+其他。例：If you had studiedharder last term, you could have passed exam.
3．表示对将来事实实现的可能性不大的假设。
其句子结构为：
从句：If+主语+should (were to )+动词原形+其他
主句：主语+would (could, should, might)+动词原形
例：If he were to go tomorrow. He might tell you.
(二) 从句和主句要根据各自发所生的时间选用符合具体时间的虚拟语气形式
1． 从句表示过去，主句表示现在。
If they had stared the early morning yesterday, they would behere now.
2． 从句表示将来，主句表示过去。
If I were not to make a preparation for my experiment thisafternoon, I would have gone to see the film with you lastnight。
3． 从句表示过去，主句表示将来。
If we hadn' t made adequate preparations, we shouldn' t dare todo the experiment next week。
4．从句表示将来，主句表示现在。
If we shouldn' t have an exam this afternoon. I would go shoppingnow.
二、动词wish后宾语从句中的虚拟语气
1． 用wish表示现在的祝愿和报歉。
其句子结构为：宾语从句的谓语be和were(was)，实义动词用过去式。例：I wish they were at homethis time.
2． 用wish表示对过去事情的遗憾。
其句子结构为：宾语从句的谓语用过去完成时或could+现在完成时。例：I wish I hadn' t hurt him somuch。
3． 用wish表示对将来事情的愿望。
其句子结构为宾语从句的谓语为would/could/might+动词原形。例：I wish I might be able tocome tomorrow 。
三、 可以引起与事实相反的方式状语从句，用虚拟语气
由as if、asthough引起的与事实相反的句子，不论主句的谓语是现在时或者说过去时，其谓语表示的时间概念和句子结构，都基本上与wish后的宾语从句相同。例：
John pretends as if he didn' t know the thing at all, but in facthe knows it very well.
(用过去式表示与现在事实相反的假设)
The old man looked at the picture, he felt as though he had goneback to time 20 years ago.
（用过去完成式表示与过去相反的事实）
They talked and talked as if they would never meet again(would+动词原形，表示与将来事实相反)
四、在表示建议、命令、要求、忠告等动词的后面，其宾语从句的谓语用“should+动词原形”表示虚拟语气
表示“要求”的：ask, desire, request, demand, require, beg
表示“提议、劝告、建议”的：move, prpose, suggest, recommend, advise,vote
表示“决定、命令”的：decide, order
表示“主张”的：maintain, urge
表示“同意、坚持”的：consent, insist
例：The doctor suggested that he (should) try to lose hisweight.
He insisted that we (should ) tell him the news.
上述动词的名词形式，demand, desire, requirment, advice, order, decision,recommendation, suggestion, 以及necessity, preference, plan, motion,idea等名词，其后的表语从句或同位语从句，也用“should+动词原形“表示虚拟语气。现代英语，特别是美国英语，常省去“should”，例：
The advice is that we (should) leave at once.
He idea that we (should)visit Great Wall was warmly welcomed.
五、在“It is(was)+形容词（或过去分词）+that……”结构中，主语从句的谓语也用“should+原形动词“表虚拟语气
美国英语中省去should, 常用的形容词和过去分词有：
表示“要求”的：required, demanded, requested, desired, desirabl。
表示“建议”的：suggested, recommended,
表示“迫切、紧近、重要”的：imperative, urgent, necessary, essential,important, vital
表示“适当、较好”的：appropriate, advisable, better, preferable
表示“可能”的：probable, possible表示“命令”的：ordered
例：It was necessary that we (should) make everything ready aheadof time.
It is required that nobody (should)smoke here.
六、由下列名词或短语引导，或含有某些词的从句中应用的虚拟语气
1．“Iest 以免、惟恐”引导的从句用“shuld+动词原形”。
He took a map with him lest he (should ) lose his wagthere.
2．“whether不管、无论”引导的让步状语从句，有时用动词原形。
All things, whether you know or don' t know, exist in theworld.
3．用“would rather/had rather' would just assoon"表示“宁愿、但愿”，后面的宾语从句谓语用过去式或动词原形表示对将来的要求，用过去时表示对现在的愿望，用过去完成时表示对过去做的事的懊悔。
Don' t live in the world, I would rather( I would just as soon)you die.
I would rather you go tomorrow.
I would rather everything hadn' t happened in the past.
4．用“had hoped”表示原来希望做到而实际上未能实现的事情，其宾语从句的谓语用“would+动词原形”。
I had hoped that she would go to the U.S. and study there, butshe said she liked to stay in China.
5．在“Itis（high/about）time+that”引导的定语从句中，定语从句的主谓语用一般过去时，偶尔也可以用would(或should)+动词原形，或hadrather (would rather)+动词原形。
It is hihg (about)time that we left/should leave/ had betterleave/had rather leave/ were leaving.(注意与“This is thefirst/second…time”后从句中用现在完成时的区别。
6．用“without/but for/in the absence of ”表示“要不是”，“如果没有”（相当于if itwere not for…）表示条件时，句中一般用虚拟语气。（也可用陈述语气）
Without your help, I couldn' t finish my work on time.
In the absence of water and air, nothing could live.
7．由“providing (that)/ provided (that)/on condition that/ in orderthat”引导的条件从句或目的从句，根据情况，可用虚拟语气。（有时也可用陈述语气）
They are willing surrender provided they are given freepassage.
8．在if引导的虚拟条件句中，若有were, had, should, 在书面语中可省去if,将were等提到主语前，形成倒装。
Should there be a good film tomorrow. I would go to the theatrewith you.
Were it not for your help. I wouldn' t be succeed.
虚拟语气专项练习
1. You didn’t let me drive. If we _____ in turn, you _____ sotired.
A. drove; didn’tgetB.drove; wouldn’tget
C. were driving; wouldn’tgetD. had driven; wouldn’t have got
2. When a pencil is partly in a glass of water, it looks as if it_____.
A.breaksB. hasbrokenC.were brokenD. had been broken
3. _____ it rain tomorrow, we should have to put off the visit tothe Yangpu Bridge.
A.WereB.ShouldC.WouldD. Will
4. Jane’s face suggested that she _____ ill, and her parentssuggested that she _____ a medical examination.
A. be; shouldhaveB. was;haveC. should be; had D. was; has
5. Without electricity human life _____ quite differenttoday.
A.isB. willbeC. would havebeenD. would be
6. I told Sally how to get there, but perhaps I _____ forher.
A. had to write itoutB. must have written it out
C. should have written itoutD. ought to write it out
7. I didn’t see your sister at the meeting. If she _____, she wouldhave met my brother.
A. hascomeB.didcomeC.cameD. had come
8. --If he _____, he _____ that food.
--Luckily he was sent to the hospitalimmediately.
A. was warmed; would nottakeB. had been warned; would not have taken
C. would be warned; had nottakenD. would have been warned; had not taken
9. The two strangers talked as if they _____ friends foryears.
A. shouldbeB. wouldbeC. havebeenD. had been
10. Without the air to hold some of the sun’s heat, the earth atnight _____, too cold for us to live.
A. would be freezingcoldB. will be freezing coldly
C. would be frozencoldD. can freeze coldly
11. --Have you ever been to Beijing?
--No, but I wish I_____.
A.haveB.willC.doD. had
12. If only he _____ quietly as the doctor instructed, he would notsuffer so much now.
A.liesB.layC. hadlainD. should lie
13. If I _____ you, I would ask him to stay.
A.wasB. wouldbeC.weD. am
14. If it hadn’t rained last Sunday, we _____ picnicking.
A. couldgoB. could have gone C.wentD. would go
15. Everybody would be very happy if the hot summer _____tomorrow.
A. shouldfinishB. wouldfinish
C. were to befinishedD. finishes
16. If only I _____ your advice!
A. hadtakenB.tookC. wouldtakeD. have taken
17. If it _____ yesterday, we could play football on the sportsground now.
A. didn’tsnowB. hasn’tsnowedC. hadn’tsnowed D.weren’t snowing.
18. If he came here at this moment, I _____ him.
A. wouldcriticize B. willcriticizeC. shall criticize D. were to criticize
19. I wish I _____ the meeting last week.
A. couldattendB.attendedC. have attended D. could have attended
20. He’s always talking like that, as if the whole world _____tohim alone.
A. hadbelongedB.belongedC.were belonging D. were belonged
21. The TV play for tonight won’t be interesting. Even if it _____,I might not have time for it.
A. wouldbeB.beC.hadbeenD. were
22. Without your help, I _____ in my English study.
A. would not havesucceededB. hadn’t succeeded
C. will notsucceedD. won’t have succeeded
23. The workers in France demanded that the their pay _____ fromthe following week on.
A. would beraisedB. wasraisedC. beraisedD. raised
24. My suggestion is that we _____ the sports met.
A. would putoffB. should putoffC. puttedoffD. be put off
25. The monitor made a proposal that the whole class _____thematter.
A.discussedB. woulddiscussC. bediscussedD. discuss
26. It is necessary that our drinking water _____ cleaner.
A. should bemadeB. ismadeC. would bemadeD. was made
27. It is high time that our child _____ to do somehousework.
A.learnedB.learnC. willlearnD. would learn
28. They stopped at Hangzhou so that they _____ the WestLake.
A. willvisitB. canvisitC. mayvisitD. might visit
29. _____ it _____ for your help, I couldn’t have make anyprogress.
A. Were;notB. Had; notbeenC. Should; notbeenD. Did; be
30. You are late again. You _____ here earlier.
A. shouldcomeB.willcome
C. should havecomeD. will have come
31. Don’t come this afternoon. I’d rather you _____ tomorrow.
A.comeB. tocomeC.cameD. will come
32. He took his raincoat with him lest it _____.
A.rainedB. shouldrainC. wouldrainD. will rain
33. John was very busy last week, otherwise, he _____ to attend themeeting.
A. would havecomeB. wouldcomeC. shouldcomeD. came
34. _____ I to tell her about it, she would be very glad.
A.ShouldB.WouldC.WereD. Might
35. Without sunlight or water or air, there _____ no life on theearth.
A. willhaveB. wouldbeC. shouldbeD. must be
36. It was ordered that no smoking _____ in the library.
A. isallowedB. beallowedC. shouldallowD. will be allowed
37. _____ I known he was in trouble, I might have managed to helphim.
A.IfB.WhenC.UnlessD. Had
38. You _____ there by taxi yesterday, it is not far fromhere.
A. couldn’t havegoneB. should have gone
C. needn’t havegoneD. mustn’t have gone
39. I would have gone there with you but I _____ too tiredthen.
A.wereB. hadbeenC.wasD. have been
40. --Did you go to see the football match yesterday?
--No, I didn’t feel well, butI would have gone if I _____.
A.didB.haveC.wouldD. had
41. _____the friendship between us last forever!
A.CouldB.WillC.MayD. Wish
42. --Where have you been?
--I got caught in traffic;_____ I could have been here soon.
A.otherwiseB.howeverC.thoughD. anyway
43. If my lawyer _____ here last Saturday, he _____ me fromgoing.
A. had been; would havepreventedB. had been; would prevent
C. were; wouldpreventD. were; would have prevented
44. If it _____ for the snow, we _____ the mountainyesterday.
A. were not; could haveclimbedB. were not; could climb
C. had not been; could haveclimbedD. had not been; could climb
45. We _____ last night, but we went to the concert instead.
A. must havestudiedB. mightstudy
C. should havestudiedD. would study
46. --There were already five people in the car but they managed totake me as well.
--It _____ a comfortablejourney.
A. can’tbeB. shouldn’tbe
C. mustn’t havebeenD. couldn’t have been
47. I was really anxious about you. You _____ home without aword.
A. mustn’tleaveB. shouldn’t have left
C. couldn’t haveleftD. needn’t leave
48. _____ your letter, I would have started off two days ago.
A. If Ireceived B.Should I receive C. If I could havereceived D. Had I received
49. It is strange that she _____ so.
A.thinkB.thinksC. willthinkD. thought
50. He suggested that the meeting _____ put off.
A. notbeB. shouldnotC.wouldn’tD. be not
51. She would rather ____ more money on books _____ onclothes.
A. cost;notB. to spare;don’t C. pay;thanD. spend; than
52. What would have happened if you _____ her child?
A. hadn’thelped B.couldn’thelpC. wouldn’t help D. didn’t help
53. If I _____ with her last summer, I _____ with her now.
A. worked; am getting on verywellB.had worked; would get on very well
C. had worked; would have got on verywell D. had worked; will get onvery well
54. The old professor gave orders that the experiment _____ before6.
A. wasfinishedB. will finis C. befinished D.shall be finished
55. The thief closed his eyes _____ he _____ dying.
A. even if;wasB. though; wouldbe C. when;had been D. as if; were
56. I wish _____ my uncle yesterday.
A. hadmetB. wouldmetC.metD. have met
57. Without his help, we _____ such rapid progress.
A. don’tmakeB. wouldn’tmakeC. didn’tmakeD. wouldn’t have made
58. _____ so busy, she would come to help you.
A. Should mydaughterB. Was my daughter not
C. If my daughter werenotD. If my daughter isn’t
59. If you _____ any problem, please don’t hesitate to ask yourteacher.
A.haveB. would haveC. are going tohaveD. will have
60. What do you think of the suggestion that she _____ at themeeting last week?
A. shouldmakeB.makeC.madeD. A or B
61. If only I _____ to my parents’ advice?
A.listeningB.listenC. am listening D. hadlistened
62. But for the snow, we _____ earlier.
A. willarriveB. should havearrived C.arriveD. arrived
63. Here’s an umbrella in case you _____ it.
A. shoulduseB.neededC.needingD. to need
64. It is natural that he _____ his mind.
A.changesB.changingC.changeD. to change
65. It is a pity Mr. Zhang isn’t here. If he _____, my parentswould be happier.
A.comesB. hascomeC.cameD. had come
66. _____ you succeed and _____ you be healthy.
A. May;mayB. Wish;wishC. Hope;hopeD. Should; may
67. It’s high time he _____ home.
A.goesB.wentC. willgoD.is going to go
68. I hoped _____ my letter.
A. her toanswerB. that she would answer
C. that she willanswerD. her answering
69. I was very busy yesterday, otherwise I _____ to themeeting.
A.cameB. wouldcomeC. hadcomeD. would have come
70. If she knew as much about music as you do, my daughter _____much better.
A.playB. mustplayC. willplayD. would play
71. “Jane wants to see you tomorrow.”
“I would rather she _____today than tomorrow.”
A.comesB. shouldcomeC.comeD. came
72. The secretary listened carefully _____ he might discoverexactly what she wanted.
A. so asthatB. incaseC. in orderthatD. providing
73. Supposing the weather _____ bad, where would they go?
A. willbeB.isC.wereD. be
74. Without the leadership of the Party, there _____ no NewChina.
A. wouldbeB. hasbeenC.wasD. should be
75. The work would require that _____ at 5 every morning.
A. she has been there B. she wasthereC. she bethereD. she will be there
76. The little hero’s pale face suggested he _____ dead.
A.isB.wasC. shouldbeD. be
77. Galileo insisted that the earth _____ round the sun.
A. shouldmoveB.moveC.movesD. A or B
78. The rice _____ if you had been more careful.
A. wouldn’t beburningB. would not burn
C. wouldn’t have beenburntD. would not burnt
79. _____ I known it, I should have told him.
A.HaveB.HadC.HavingD. If
80. If Alice _____ this afternoon, the meeting should be putoff.
A. would notcomeB. might notcomeC. should not come D. could not come
81. If you had gone to a doctor, you _____ all right now.
A.areB.wereC. would havebeenD. would be
82. It is necessary that we _____ a foreign language.
A. mustmasterB. ought tomasterC.masteredD. should master
83. My idea is that we _____ to our plan.
A. muststickB. ought tostickC. shouldstickD. will stick
84. He _____ into trouble if he had taken our advice.
A. would have notgotB. Had notgot
C. wouldn’t havegotD. didn’t get
85. I didn’t see her in the meeting room this morning. She _____ atthe meeting.
A. mustn’t havespokenB. shouldn’t have spoken
C. needn’t havespokenD. couldn’t have spoken
86. One ought _____ for what one hasn’t done.
A. not to be punished B. to not bepunishedC.to not punished D. not be punished
87. If you really want yourself to be in good health, you must_____ always _____ so much.
A. not; be smoking B. not;have smoked C. not; tosmokeD.be not; smoking
88. With so much work on hand, you _____ to see the game lastnight.
A. mustn’tgoB. shouldn’tgo
C. couldn’t havegoneD. shouldn’t have gone
89. Most of the students felt rather disappointed at the Englishparty. They say that it _____ better organized.
A. hadbeenB. had tobeC.must havebeenD. could have been
90. I’m surprised that he _____ in the exam.
A. shouldfail B. wouldhavefailedC.may havefailedD.should have failed
答案
1-10 DCBBD CDBDA 11-20 DCCBA ACADB 21-30 DACBDAADBC 31-40 CBACB BDCCD 41-50 CAACC DBDAA 51-60 DABCD ADCAC 61-70DBACD ABBDD 71-80 DCCAC BCCBC 81-90 DDCCD AADDD
