虚拟语气的用法大全【优秀8篇】

虚拟语气在条件从句中的用法 篇一

（一）形式 　　注：

1、在从句中，be动词多用were的形式。在口语中，如果主语是第一、第三人称单数的话，be动词可用was，但人们总是说：If I were you.。.

2、主句中的谓语可以由would，should，could和 might这四个不同的情态动词来构成。

3、与将来事实相反的条件从句中，谓语有三种不同的形式：过去式、were +to do或should +do。 　　例句1：If I were you，I would study hard.我要是你的话，我就会好好学习。（与现在事实相反） 　　例句2：If I had studied hard，I would have passed CET-6 last semester.我要是早就好好学习的话，那么我上个学期就通过六级考试了。（与过去事实相反） 　　例句3：If Iwere to pass CET-6，I would treat you to dinner at KFC.我要是过了六级考试，就请你去吃肯德基。（与将来事实相反）

（二）省略/倒装 　　如果在虚拟从句中包含有一个助动词、情态动词、动词be或have，则可把if省略，把上类动词提到主语之前，使用倒装语序。

例句4：Had it not been for the PLA，we wouldn’t have been able to beat the flood.4要不是人民解放军，我们是无法战胜洪水的。

例句5：Were he here now，he would certainly help me.5他要是在这里肯定会帮我的忙。 　　注4：例句4中的从句部分出现了否定词not，如果把该句还原成正常语序，应该是： 　　If it hadn’t been for the PLA，we wouldn’t have been able to beat the flood.

但是一旦句子发生了省略，就必须把hadn’t分开，否定词not还原，放在主语之后，不可写成Hadn’t it b

if引导条件状语从句的用法 篇二

某事很可能发生，条件是可能存在的，主句中某种情况发生的概率也是很高的。如：

If you ask him,he will help you.如果你请他帮忙，他会帮你的。

If you fail in the exam,you will let him down.如果你考试不及格，你会让他失望的。

If you have finished the homework,you can go home.如果你作业做完了就可以回家了。

另外，if从句还表示不可实现的条件或根本不可能存在的条件，也就是一种虚拟的条件或假设。从句多用一般过去时或过去完成时，表示对现在或过去的一种假设。如：

If I were you,I would invite him to the party.如果我是你，我会邀请他参加聚会。

I would have arrived much earlier if I had not been caught in the traffic.要不是交通堵塞，我本会来得早一些。

另外你还要注意if 条件句的时态搭配

1.if从句用一般现在时，主句用一般将来时

If he runs he’ll get there in time.如果他用跑的，他就会及时赶到那儿。

The cat will scratch you if you pull her tail.如果你拉猫的尾巴，它就会抓你。

2.if从句用一般现在时，主句用may/might/can

If the fog gets thicker the plane may/might be diverted.如果雾在大一些，飞机可能就会改在别的机场降落。

If it stops snowing we can go out.如果雪停了，我们就可以出去。

3.if从句用一般现在时，主句用must/should

If you want to lose weight you must/should eat less bread.如果你想减肥，你必须少吃面包。

4.if从句用一般现在时，主句用一般现在时

If you heat ice it turns to water.（也可用will turn）如果把冰加热，它就会化成水。

5.if从句用现在进行时，主句用一般将来时

If you are looking for Peter you’ll find him upstairs.如果你是在找彼得，上楼就会找到他。

6.if从句用现在完成时，主句用一般将来时

If you have finished dinner I’ll ask the waiter for the bill.如果你吃完了，我就叫服务生来算账

虚拟语气专项练习题解析 篇三

1、 If I ____ where he lived， I ____ a note to him.

A. knew， would

B. had known， would have sent

C. know， would send

D. knew， would have sent

2、 If they ____ earlier than expected， they ____ here now.

A. had started， would be

B. started， might be

C. had started， would have been

D. will start， might have been

3、 I didn't know his telephone number. ____ it， I ____ then.

A. Had I known， would ring him up

B. Should I know， would have rung him up

C. If I knew; would ring him up

D. Had I known; would have rung him up

4、 Mary is ill today. If she _____， she ____ absent from school.

A. were not ill， wouldn't be

B. had been ill， wouldn't have been

C. had been ill， should have been

D. hadn't been ill， could be

5、 Were I to do it， I ________ it some other way.

A. will do B. would do C. would have done D. were to do

6、 I ________ him the answer ________ possible， but I was so busy then.

A. could tell， if it had been

B. must have told， were it

C. should have told， had it been

D. should have told， should it be

7、 Without your help， we________ so much.

A. won't achieve B. didn't achieve C. don't achieve D. wouldn't have achieved

8、 You didn't take his advice. ________ his advice， you ________ such a mistake.

A. Had you taken， wouldn't have made

B. If you had taken， would make

C. Were you lo take， shouldn't have made

D. Have you taken， won't have made

9、 We wish we ____ what you did when we were at high school.

A. did B. could have done C. have done D. should do

10、 She wishes she ____ to the theatre last night.

A. went B. would go C. had gone D. were going

11、 Tom is very short now. His mother wishes that he ________ be tall when he grows up.

A. could B. should C. would D. were able to

12、 My sister advised me that I ________ accept the invitation.

A. could B. must C. should D. might

13、 He asks that he ________ an opportunity to explain why he's refused to go there.

A. is given B. must give C. should give D. be given

14、 Do you think of Wang Fang's suggestion that he ________ Mr. Li to the party?

A. will invite B. have invited C. is invited D. invite

15、 I insisted that he ________ at once.

A. be gone B. go C. would go D. might go

16、 Li Ming insisted that he ________ anything at all.

A. hadn't stolen B. shouldn't steal C. doesn't steal D. steal

17、 It is quite natural that my coming late again ________ them very angry.

A. had made B. would make C. makes D. make

18、 He acted as if he ________ everything in the world.

A. knew B. knows C. has known D. won't know

19、 Read it aloud so that I ________ you clearly.

A. may hear B. will hear C. hear D. have heard

20、 They got up early in order that they ________ they first train.

A. caught B. will catch C. might catch D. shall catch

21、 I am sorry that he ________ in such poor health.

A. are B. shall be C. were D. should be

22、 That is a good book. You ________ it yesterday.

A. could buy B. should buy C. should have bought D. bought

23、 It is high time we ________ home.

A. will go B. would go C. have gone D. went

24、 I'd rather that you ________ home.

A. went B. have gone C. will go D. had gone

25、 If only I _________ to the lecture!

A. listen B. will listen C. am listening D. had listened

26、 —— If he_____， he ______ that food.

---- Luckily he was sent to the hospital immediately.

A. was warned， would not take

B. had been warned， would not have taken

C. would be warned， had not taken

D. would have been warned， had not taken

27、 I didn't see your sister at the meeting. If she _________， she would have met my brother.

A. has come B. did come C. came D. had come

28、 Without electricity， human life ________ quite different today.

A. is B. will be C. would have been D. would be

29、 He ________ you more help， even though he was very busy.

A. might have given B. might give C. may have given D. may give

30、 If city noises _______ from increasing， people _______ shout to be heard even at the dinner table 20 years from now.

A. are not kept， will have to

B. are not kept， have to

C. do not keep， will have to

D. do not keep， have to

31、 Mike's father， as well as his mother， insisted that he ________ home.

A. stayed B. could stay C. has stayed D. stay

32、 Mr. Smith insisted that he ________ the work all.

A. had done B. have done C. did D. so

33、 Jane would never have gone to the party ________ that Mary would come to see her.

A. has she known B. had she known C. if she know D. if she has known

34、 If you had enough money， what ________?

A. will you buy

B. would you buy

C. would you have bought

D. will you have bought

35、 If you ________ that film late last night， you wouldn't be so sleepy.

A. didn't see B. haven't seen C. wouldn't have seen D. hadn't seen

36、 Our monitor requested that ________.

A. all the clastudied more carefully the problem

B. the problem was more carefully studied

C. with great care the problem could be studied

D. all the clastudy the problem more carefully

37、 —— Would you have called her up had it been possible?

Yes, but I ________ busy doing my homework.

A. was B. were C. had been D. would be

38、 His tired face suggested that he ________ really tired after the long walk.

A. had been B. was C. be D. should be

39、 It is important that we ________.

虚拟语气的时态 篇四

一、过去式：

if 从句：had done

英语语法：虚拟语气的时态

主句：情态动词(would，could，might，should)+have done

英语语法：虚拟语气的时态

二、现在式：

if 从句：did/were

英语语法：虚拟语气的时态

主句：情态动词(would，could，might，should)+do

英语语法：虚拟语气的时态

三、将来时：

if 从句：①should/shall do

②were to do

③did/were

英语语法：虚拟语气的时态

6

主句：情态动词(would，could，might，should)+do

虚拟语气的用法 篇五

虚拟语气是一种特殊的动词形式，用来表示说话人所说的话并不是事实，而是一种假设、愿望、怀疑或推测。判断是真实条件句还是非真实条件句。只有在非真实条件句中才使用虚拟语气。通过句子意思，看假设的条件是否能够实现，能够实现是真实条件句，不能使用虚拟语气；假设的条件不能实现则是非真实条件句，要用虚拟语气。判断这个假设是与哪个事实相反。

通常有三种情况：①与过去事实相反。②与现在事实相反。③与将来事实可能相反。

I: 最基本的虚拟语气句型:

1、 虚拟现在时表示与现在事实相反的假设，其if 从句的谓语形式用动词的过去式(be 一般用were)，主句用would/ should/ could/ might +动词原形。If places were alike, there would be little need for geographers.如果各个地方都一样，就不需要地理学家了。

2、 虚拟过去时是表示与过去事实相反的假设，if 从句的谓语形式用过去完成时即had+过去分词，主句用would / should / could / might + have +过去分词。If he had known your address yesterday,he would have telephoned you.

3、 虚拟将来时是表示对将来实现的可能性很小的或不确定的假设。If从句的谓语形式用一般过去式或用were to / should +动词原形，主句用would / should/could/ might +动词原形。If he were to leave today, he would get there by Friday

4、 省略if 采用倒装语序的条件句。有时可以把含有助动词、情态动词、be或have的虚拟条件句中的连词if省去，而将had ， should, were 等词提到主语之前，即用倒装结构。If he had worked harder, he would have got through the exams.==>Had he worked harder, he would have got through the exams.If he were to leave today, he would get there by Friday.==>Were he to leave today, he would get there by Friday.If I were in your place, I wouldn’t do that.==>Were I in your place, I wouldn’t do that.

5、 有时虚拟条件句并没用if 从句表示出来，而是用介词短语(otherwise, or, without, but for)、上下文或其它方式来表示。如：We didn't know his telephone number; otherwise we would have telephoned him. Without you help, I wouldn’t have achieved so much. But for （“要不是。”的意思）your help, I would not have succeeded.

II: 虚拟语气在从句中用should的情况:

1、 在表示建议，要求，命令，想法的动词后的从句里， 用should + 动词原形， should 可以省略。 如 advise, agree, command, decide, demand, determine, grant, indicate, insist, order, prefer, propose, request, require, stipulate, suggest, urge, vote.常考到的是: suggest, advise, demand, require, propose, insist, order, request.

His doctor suggested that he (should) take short leave of absence.

The author proposed that TV (should) be turned off at least one hour every day.

2、 在表示建议，要求，命令，想法的名词后的从句里， 用should + 动词原形， should可以省略。 如 advice, decision,agreement, command, decree, demand, determination, indication, insistence, order, preference, proposal, request, requirement, stipulation etc.

It was Bill’s suggestion that everyone (should) have a map.

His suggestion was that everyone (should) have a map.

He gave us a suggestion that everyone (should) have a map.

3、 在It is/was +形容词后的that 从句中用should的结构， should 可以省略。 这类形容词常见的有: advisable, anxious, compulsory, crucial, desirable, eager, essential, fitting, imperative（绝对必要）， impossible, improper, important, natural, necessary, obligatory, possible, preferable, probable, recommended, urgent, vital etc.

It‘s natural that she (should) do so.

It is essential that we (should) tell her the news.

4、 在 lest 和 for fear that（以免），in case（以防）从句中用should, should 可以省略。

She walked quietly lest she (should) wake up her roommates.

Have your gun ready in case we should need it.

III: wish 后的 that 从句中:

1、 表示现在或将来的愿望，从句中过去式。

I wish I knew his address.

I wish I were young.

2、 表示过去没有实现或不可能实现的愿望， 从句用过去完成式或would, could, might + have + 过去分词。

I wish you had written to him.

I wish I could have slept longer this morning, but I had to get up and come to class.

3、 如果将wish改成wished, 其后that 从句中动词的形式不变。

4、 如果that 从句中用would ， 一般表示 对现状不满或希望未来有所改变或请求

I wish he would answer my letter.

I wish prices would come down.

I wish you would help me.

I wish you would stop asking silly questions.

IV: 在 It’s about/ high/ first(second, third etc)time 后的that 从句中，用过去式。表示“该是做什么的时候了”

It is about time you were in bed.

It is high time we left.

It is the first time I came here.

V: 在would rather, would sooner, would just as soon 后的that从句中，用过去式或过去完成式，表示“宁愿做什么”

I would rather he came tomorrow than today.

John would rather that she had not gone to the party yesterday evening.

VI: 在if only（“如果。就好了”的意思） 感叹句中，谓语动词与wish宾语从句的虚拟形式相同。

If only he didn’t drive so fast!（现在）

If only she had asked someone’s advice.（过去）

If only the rain would stop.（将来）

VII: 在as if / as though 从句中，表示和现在事实相反或对现在情况有所怀疑，用过去式；表示过去想象中的动作或情况， 用过去完成式。

He speaks as if he were on the spot.

She spoke to me as if I were deaf.

This device operated as though it had been repaired.

注: 1. 在 as if / as though 句中， 如果有可能成为事实， 用陈述语气。

He looks as if he is going to be ill.

2、 在 insist 后的从句中， 如果是坚持自己， 用陈述语气， 坚持别人做什么事情， 用虚拟语气。

She insists that she is right.

She insisted that I should finish the work at once.

虚拟语气专项练习题解析 篇六

1、 If my lawyer _______ here last Saturday， he _______ me from going.

A. had been； would have prevented

B. had been； would prevent

C. were； would prevent

D. were； would have prevented

解析：A．本题考查虚拟语气。因为从句表示与过去事实相反的`假设，故从句谓语动词用过去完成时，而主句谓语动词用would have +过去分词形式。

2、 If I had worn my overcoat， I _______cold.

A. won’t have caught

B 。couldn’t have caught

C. won’t catch

D. wouldn’t catch

解析：B．本题考查虚拟条件句中主句谓语动词的使用。因为从句用了过去完成时，可知主句谓语动词用would / could have +过去分词形式。根据句意，可知选B.

3、—If he ______ ， he ______ that food.

—Luckily he was sent to the hospital immediately.

A. was warned； would not take

B. had been warned； would not have taken

C. would be warned； had not taken

D. would have been warned； had not taken

解析：B. 根据答语，可知本题考查与过去事实相反的虚拟语气。故从句谓语动词用过去完成时，而主句谓语动词用would have +过去分词形式。

4、 I didn’t see your sister at the meeting. If she _______， she would have met my brother.

A.has come

B. did come

C. came

D. had come

解析：D． 根据句意“在会上我没有看到你的姐姐。如果她来的话，她就见到我哥哥了”可知，这是考查对过去事实的虚拟。主句用could have done，故从句谓语动词应该用过去完成时。

5、 “I still haven’t thanked Aunt Lucy for her present.” “It’s time you _____.”

A. do

B. did

C. had

D. would

解析：选B。It’s time you did 为 It’s time you thanked Aunt Lucy for her present 之略。按照英语语法，it’s time 后从句通常要用过去式。

6、 If I hadn’t been lucky enough to meet you. I really _____ what I would have done.

A. don’t know

B. hadn’t known

C. wasn’t knowing

D. wouldn’t know

解析：选A。虽然前有虚拟条件句， 后有使用了虚拟语气的宾语，但 I don’t know 却宜用一般现在时，因为 I don’t know 表述的是现在的真实情况，句意为“我要不是有幸遇到你，我真不知（指现在不知）我会做出什么蠢事来”。

7、 “I’ve told everyone about it.” “Oh, I’d rather you _____.”

A. don’t

B. hadn’t

C. couldn’t

D. wouldn’t

解析：选B。I’d rather 后接从句时，从句谓语的时态规律是：用过去式表示现在或将来，用过去完成式表示过去。

8、 It has been raining for a day, but even though it hadn’t rained, we _____ there by tomorrow.

A. can’t get

B. won’t get

C. hadn’t got

D. wouldn’t get

解析：选A。we can’t get there by tomorrow 为客观事实，故宜用陈述语气。

9、 “Do you know his address?” “No, I also wish I _____ where he _____.”

A. knew, live

B. knew, lives

C. know, lives

D. know, lived

解析：选B。第一空填 knew，因为 I wish 后的宾语从句要用虚拟语气（即用过去式表示现在的想法）；第二空要填lives，即用陈述语气，因为 where he lives 是一个客观事实，而不是 I wish 的内容。

10、 “Isn’t 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 begun

解析：选C。It’s time… / It’s high time… / It’s about time… 等后接从句时，从句谓语通常用过去式。

11、 It is hard for me to imagine what I would be doing today if I ____ in love, at the age of seven, with the Melinda Cox Library in my hometown.

A. wouldn’t have fallen

B. had not fallen

C. should fall

D. were to fall

解析：选 B。此题涉及错综时间虚拟条件句，主句与现在事实相反，条件句与过去事实相反。句意为：要不是在七岁时就迷上了 Melinda Cox 图书馆，我真不能想像我如今会在做什么。

12、 He hesitated for a moment before kicking the ball, otherwise he ____ a goal.

A. had scored

B. scored

C. would score

D. would have scored

解析：选 D。这是otherwise 引出的含蓄虚拟语气，再根据前面的 hesitated 可进一步知道这是与过去事实相反的虚拟语气，由此可推知答案选 D。

13、 If only he _______ quietly as the doctor instructed, he would not suffer so much now.

A. lies

B. lay

C. had lain

D. should lie

解析：选 C。if only 意为“要是……就好了”，其后的句子谓语要用虚拟语气，同时根据 as the doctor instructed 中的过去时态可知从句是与过去事实相反，故选 C。

14、 Without the air to hold some of the sun’s heat, the earth at night ____ for us to live.

A. would be freezing cold

B. will be freezing coldly

C. would be frozen cold

D. can freeze coldly

解析：选 A。without 引出的介词短语为一个与现在事实相反的含蓄条件句。

15、 Yesterday, Jane walked away from the discussion. Otherwise, she ____ something she would regret later.

A. had said

B. said

C. might say

D. might have said

解析：选 D。otherwise 在此相当于 if she had not walked away from the discussion，即暗示一个与过去事实相反的虚拟条件句。

虚拟语气专项练习题解析 篇七

1.I enjoyed the movie very much. I wish I _____ the book from which it was made.

A. have read　　　　　　　　 B. had read

C. should have read　　　　 D. are reading

2.You are late. If you _____ a few minutes earlier, you _____ him.

A. come; would meet　　　　　B. had come; would have met

C. come; will meet 　　　　　D. had come; would meet

3.The two students talked as if they _____ friends for years.

A. should be　　　　　 B. would be

C. have been　　　　　 D. had been

4.It is important that I _____ with Mr. Williams immediately.

A. speak　　　　　　　B. spoke

C. will speak　　　　 D. to speak

5.He looked as if he _____ ill for a long time.

A. was　　　　　 B. Were C. has been　　 D. had been

6.If the doctor had come earlier, the poor child would not _____.

A. have laid there for two hours 　　　　　　 B. have been lied there for two hours

C. have lied there for two hours　　　　　　　D. have lain there for two hours

7.I wish that I _____ with you last night.

A. went　　　　 　B. could go

C. have gone　　　D. could have gone

8.Let’s say you could go there again, how _____ feel?

A. will you　　　　　B. should you

C. would you　　　　 D. do you

9.I can’t stand him. He always talks as though he _____ everything.

A. knew 　　　　　　　　　　 B. knows

C. has known　　 　　　　　　D. had known

10._____ the fog, we should have reached our school.

A. Because of　 　B. In spite of

C. In case of　　 D. But for

11.If you had told me in advance, I _____ him at the airport.

A. would meet　　　　　　 B. would had met

C. would have met　　　　 D. would have meet

12.Mike can take his car apart and put it back together again. I certainly wish he_____ me how.

A. teaches 　　　　　　　　 B. will teach

C. has taught　　　　　　　 D. would teach

13.I would have told him the answer, had it been possible, but I _____ so busy then.

A. had been　　　　　　　B. were

C. was　　　　　　　　　 D. would be

14.He’s working hard for fear that he _____.

A. should fall behind　　　　B. fell behind

C. may fall behind　　　　　 D. would fallen behind

15.If it _____ another ten minutes, the game would have been called off.

A. had rained　　　　　B. would have rained

C. have seen　　　　　 D. rained

16.He suggested that they _____ use a trick instead of fighting.

A. should　　　　　　　 B. would

C. do　　　　　　　　　 D. had

17.My father did not go to New York; the doctor suggested that he _____ there.

A. not went　　　　　 B. won’t go

C. not go　　　　　　 D. not to go

18.I would have gone to the meeting if I _____ time.

A. had had　　　　　 B. have had

C. had　　　　　　　 D. would have had

19.Would you rather I _____ buying a new bike?

A. decided against　　　B. will decide against

C. have decided　　　　 D. shall decide against

20.You look so tired tonight. It is time you _____.

A. go to sleep　　　 　　　B. went to sleep

C. go to bed　　　　　　　 D. went to bed

21、—Why didn’t you buy a new car?

—I would have bought one if I _____ enough money.

A. had　　 　　　　 B. have had

C. would have　　　 D. had had

22.If she could sew, _____.

A. she make a dress 　　 　　　B. she would have made a shirt

C. she will make a shirt　　　 D. she would had made a coat

23._____ today, he would get there by Friday.

A. Would he leave　　　　 B. Was he leaving

C. Were he to leave　　　 D. If he leaves

24.His doctor suggested that he _____ a short trip abroad.

A. will take　　　　　B. would take

C. take　　　　　　　　D. took

25.The Bakers arrived last night. If they’d only let us know earlier,_____ at the station.

A. we’d meet them　　　　　　 B. we’ll meet them

C. we’d have met them　　　　 D. we’ve met them

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.We might have failed if you _____ us a helping hand.

A. have not given　　　　　B. would not give

C. had not given　　　　　 D. did not give

28.The law requires that everyone _____ his car checked at least once a year.

A. has　　 　　　　　　　　　 B. had

C. have　　　　　　　　　　　 D. will have

29.It is strange that he _____ so.

A. would say　　　　　 B. would speak

C. should say　　　　　D. will speak

30.Had I known her name, _____

A. or does she know mine?　　　　　　B. and where does she live?

C. she would be beautiful.　　　　　 D. I would have invited her to lunch.

31.He has just arrived, but he talks as if he _____ all about that.

A. know 　　　　　 B. knows

C. known　　　　　 D. knew

32.If I _____ the money, I would have bought a much bigger car.

A. possessed　　　　　　　　　 B. owned

C. had　　　　　　　　　　　　 D. had had

33.He was very busy yesterday; otherwise, he _____ to the meeting.

A. would come　　　　 　　　B. came

C. would have come　　　　　D. will come

34.The librarian insists that John _____ no more books from the library before he returns all the books he has borrowed.

A. will take　　　　　　　　　　 B. took

C. take　　　　　　　　　　　　　D. takes

35.I left very early last night, but I wish I _____ so early.

A. didn’t leave　　　　　　 B. hadn’t left

C. haven’t left　　　　　　 D. couldn’t leave

36.I do not have a job. I would find one but I _____ no time.

A. had　　 　　　　　　　　　　B. didn’t have

C. had had　　　　　　　　　　 D. have

37.I wish that you _____ such a bad headache because I’m sure that you would have enjoyed the concert.

A. hadn’t　　　　　 B. didn’t have had

C. hadn’t had　 　　D. hadn’t have

38.He insisted that we all _____ in his office at one o’clock.

A. be　　　　　　　　　 B. to be

C. would be　　　　　　 D. shall be

39.Helen couldn’t go to France after all. That’s too bad. I’m sure she would have enjoyed it if _____.

A. she’s gone　　　　　　　 B. she’ll go

C. she’d gone　　　　　　　 D. she’d go

答案：

1—5 BBDAD 　　　　　　6—10 DDCAD　　　　 　　　　 11—15 CDCAA　　　　　16—20 ACAAD

21—25 DBCCC 　　　　 26—30 DCCCD　　　　 　　　　 31—35 DDCCB 　　　　 36—39 DCAC

解析：

1.wish后面用虚拟语气，表示与过去事实相反用过去完成时。

2、条件句表示与过去事实相反，主句用过去将来完成时，从句用过去完成时。

3.as if后面如果表示真实情况就不用虚拟。

4.It is important that是主语从句的虚拟语气，从句用sb. should do的形式。

5.as if后面是真实情况，不虚拟。

6.lain是lie的过去分词，表示“躺”。

7.could have done表示“本来可以”。

8、与将来相反的虚拟语气，主句用过去将来时。

9.as if表示不可能发生的事情时用虚拟语气。

10.but for表示“要不是……的话”，通常与虚拟语气搭配使用。

11.in advance表示“事先”，表示与过去事实相反的虚拟语气。

12.wish的宾语从句表示发生在将来的愿望用过去将来时。

13.but的并列句表示真实情况，不用虚拟语气。

14.for fear that后面的状语从句用sb. should do的形式。

15、表示与过去事实相反，主句用过去将来完成时，从句用过去完成时。

16.suggest后面的宾语从句用sb. should do的形式。

17.suggest后面的从句用sb. should do的形式，should可以省略。

18、表示与过去事实相反，从句用过去完成时。

19.would rather的宾语从句用sb. did的形式。

20.It is time后面的定语从句用sb. did的形式。

21、第一个had是过去完成时，第二个had表示“有”。

22.would have done是过去将来完成时，表示与过去相反的虚拟语气。

23、这是虚拟语气的倒装形式，把if去掉，助动词提前。

24.suggest后面的从句用sb. should do的形式，should可以省略。

25、表示与过去事实相反，主句用过去将来完成时。

26、在虚拟语气中，不管什么人称，be动词都要用were的形式。

27、表示与过去事实相反，从句用过去完成时。

后面的从句用sb. should do的形式，should可以省略。

29.It is strange that是主语从句的虚拟语气，从句用sb. should do的形式。

30.had I known是与过去相反的虚拟语气的倒装形式。

31.as if表示不可能发生的事情时用虚拟语气。

32、第一个had是过去完成时，第二个had表示“有”。

经常可以搭配虚拟语气，表示与过去事实相反。

34、当insist表示“坚持认为”时不用虚拟形式。

35.wish后面用虚拟语气，表示与过去事实相反用过去完成时。

36.but的并列句表示真实情况，不用虚拟语气。

37.wish后面用虚拟语气，表示与过去事实相反用过去完成时。

38、当insist表示“坚持要求”时从句用虚拟形式。

39、表示与过去事实相反，从句用过去完成时。