一、考點聚焦
1、虛擬語氣用于條件狀語從句中
（1）表示與現(xiàn)在事實相反的假設(shè)，條件狀語從句中的謂語動詞用“過去式（be動詞的過去式用were）”，而主句中的謂語動詞用“would / should/ could / might + 動詞原形”。如：
If I were a boy, I would join the army.
If the had time, she should go with you.
（2）表示與過去的事實相反，條件狀語從句中的謂語動詞用過去完成時，主句中的謂語動詞則用“would / should / might / could + have +過去分詞”。如：
If he had taken my advice, he would have succeeded in the competition.
（3）表示與將來事實相反，條件狀語從句中的謂語動詞一般過去時或should(were to) + 動詞原形，而主句中的謂語動詞則用would / should/
could might + 動詞原形。如；
If it were to rain tomorrow, the football match would be put off.
（4）當(dāng)條件狀語從句表示的行為和主句表示的行為所發(fā)生的時間不一致時，動詞的形式要根據(jù)它所表示的時間作相應(yīng)調(diào)整。如：
If they had worked hard, they would be very tired.(從句說的是過去，主句指的是現(xiàn)在)
以下表格是虛擬語氣用于條件狀語從句中時，主句和從句謂語動詞的形式：
條件狀語從句 主 句
與過去事實相反 had + 過去分詞 should /would/could/might + have + 過去分詞
與現(xiàn)在事實相反 一般過去時(be用were) would/should/could/might + 動詞原形
與將來事實相反 一般過去時或should(were to) + 動詞原形 Would/should/cold/might + 動詞原形
有時侯在使用時可省略if,句子則可換成下列形式，即“were / had / should +主語”。如：
Were I a boy, I would join the army.
Had he taken my advice, he would have succeeded.
Were it not for the expense, I would go to Britain.
2、虛擬語氣用于名詞性從句
（1）虛擬語氣在賓語從句中的運用。
①“wish + 賓語從句”表示不能實現(xiàn)的愿望，譯為“要是……就好了”等。表示現(xiàn)在不能實現(xiàn)的愿望，從句中的謂語動詞用一般過去時；表示將來不能實現(xiàn)的愿望，從句中的謂語動詞用“would/could + 動詞原形”；表示過去不能實現(xiàn)的愿望，從句中的謂語動詞用“had + 過去分詞”或“could(should) + have + 過去分詞”。如：
I wish it were spring all the year round.
I wish I had known the answer.
I wish I could fly like a bird.
②在表示建議、要求、命令等的動詞suggest、advise、propose、demand、require、insist request、command、order等后的賓語從句中，謂語動詞用should + 動詞原形或是動詞原形。如：
She suggested we (should)leave here at once.
The doctor ordered she should be operated.
（2）虛擬語氣在同位語從句和表語從句中的運用。
作表示建議、要求、命令等的名詞advise、idea、order、demand、plan、proposal、suggestion、request等的表語從句和同位語從句，從句中的謂語動詞用“（should） + 動詞原形”。如：
His suggestion that we (should)go to Shanghai is wonderful.
My idea is that they (should)pay 100 dollars.
（3）虛擬語氣在主語從句中的運用。
在主語從句中，謂語動詞的虛擬語氣用“should + 動詞原形”的結(jié)構(gòu)，表示驚奇、不相信、理應(yīng)如此等。如：
It is necessary(important, natural, strange, etc.)that we should clean the room every day.
It was a pity (a shame, no wonder, etc.)that you should be so careless.
It will be desired(suggested, decided, ordered, requested, proposed, etc.)that she should finish her homework this afternoon.
注意：這種從句表示的是事實。如果說人對這種事實表現(xiàn)出驚奇的情感，就可用虛擬語氣。反之，如果不表示驚奇等情感，that從句也可用陳述句語氣。如：
It is pity that you can’t swim.
3、虛擬語氣在其他場合的運用
（1）虛擬語氣在as if/as though、even if/even though等引導(dǎo)的表語從句或狀語從句中，如果從句表示的動作發(fā)生在過去，用過去完成時；指現(xiàn)在狀況，則用一般過去時；指將來狀況則用過去將來時。如：
He did it as if he were an expert.
Even if she were here, she could not solve the problem.
（2）虛擬語氣用于定語從句中。
這種從句常用于句型“It is (high)time (that) … ”中，定語從句的謂語動詞用一般過去時(be用were)或should + 動詞原形，意思是“(現(xiàn)在)該……”。如：
It’s time that I picked up my daughter.
It’s high time we were going.
（3）虛擬語氣用在if only引導(dǎo)的感嘆句中。如：
If only I were a bird.
If only I had taken his advice.
（4）虛擬語氣在一些簡單句中的運用。
①情態(tài)動詞的過去式用于現(xiàn)在時態(tài)時，表示說話人謙虛、客氣、有禮貌或語氣委婉，常出現(xiàn)在日常會話中。如：
It would be better for you not to stay up too late.
Would you be kind enough to close the door?
②用于一些習(xí)慣表達法中。如：
Would you like a cup of tea?
I would rather not tell you.
二、精典名題導(dǎo)解
選擇填空
1. When a pencil is partly in a glass of water, it looks as if it _______. (NMET 95)
A.breaks B.has broken C.were broken D.had been broken
解析：答案為C。本題考查的是as if 引導(dǎo)的讓步狀語從句中的語氣問題，as if引導(dǎo)的狀語從句如果與事實一致，不用虛擬語氣，如果與事實相反，應(yīng)用虛擬語氣。題中“當(dāng)鉛筆的一部分浸在水中，鉛筆看上去好像斷了”。而實際上鉛筆并未斷，與事實相反，前半部分陳述是一般現(xiàn)在時，因而本句是對一般現(xiàn)在時的虛擬，用were broken。
2. I didn’t see your sister at the meeting. If she ___________, she would have met my brother.(NMET 94)
A.has come B.did come C.came D.had come
解析：答案為D。本題考查的是if條件句中的虛擬語氣。題意是：我在會議上沒看到你姐姐，故你姐姐沒來。因此如果“她來了”與事實相反，前面一句交代了虛擬語氣的時態(tài)是一般過去時的虛擬，所以if從句中用had+過去分詞。
3. -If he ___________, he ________that food.
-Luckily he was sent to the hospital immediately.(NMET 93)
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：答案為B。本題考查的是條件狀語從句與主句表示與事實相反時虛擬語氣的用法。根據(jù)下一句語境可知，他事先并沒有得到警告，表示過去時間的虛擬語氣，故選B。
三、專項訓(xùn)練
1. It's a pity I didn't attend the lecture,but how I wish I______.
A.did B.will C.would D.had
2. They______to get back earlier,but they missed the train.
A.had hoped B.have hoped C.hoped D.would hope
3. The teacher demanded that the exam______before eleven.
A.must finish B.would be finished C.be finished D.must be finished
4. He is talking so much about America as if he______there.
A.has been B.was C.been D.had been
5. Mother suggested that I______my homework first before watching TV.
A.did B.do C.shall do D.have done
6. His suggestion was that we______there by plane.
A.go B.to go C.should be going D.be going
7. The commander ordered that the wounded______to hospital right away.
A.to be sent B.send C.be sent D.sould send
8. If she had worked harder,she______.
A.would succeed B.had succeeded
C.should succeed D.would have succeeded
9. Without electricity,human life______quite different today.
A.is B.would be C.will be D.would have been
10. -Did Mr.Green scold her for her mistakes?
-Yes,but he______that.
A.shouldn't have done that B.should do
C.shouldn't do D.should have done
11. -Do you have a theatre ticket for tonight?
-No,but I wish I______.
A.do B.will C.have D.did
12. He______the test,but he wasn't careful enough.
A.could have passed B.were able to pass
C.must have passed D.might be able to pass
13. Without your help,we______so much.
A.will not achieve B.didn't achieve
C.would not have achieved D.don't achieve
14. -Was the housemaster strict?
-Yes,He requested that we______television on week nights.
A.must not to watch B.not watch
C.not be watching D.have not watched
15. -Why didn't you go to the dance last night?
-If I______tired,I would have.
A.haven't B.hadn't C.haven't been D.hadn't been
16. If he______,he______that foo D.
A.had been warned;would not have taken
B.was warned;would not take
C.would be warned;had taken
D.would have been warned;had not taken
17. ______for your knowledge of the language,I should have been completely lost.
A.Hadn't it been B.If it were not
C.Had it not been D.Has it been not
18. If only you______the plan.
A.had carried out B.carry out C.carrying out D.carried out
19. ______your help,I would have passed the examination.
A.Without B.With C.But for D.If I had
20. I'd rather you______there yesterday.I'd rather you______there tomorrow.
A.didn't go;went B.hadn't gone;should go
C.didn't go;should go D.hadn't gone;went
21. The woman treats the boy as if he______her son.
A.were B.are C.is D.was
22. When a pencil is partly in a glass of water,it looks as if(though)it______.
A.breaks B.were broken C.has broken D.has been broken
23. Look at the clouds.It looks as if it______rain.
A.will B.would C.is going to D.were
24. I lost my way to your house,otherwise(or)I______you about it much earlier.
A.had told B.have told C.should tell D.would have told
25. The smile on his face suggested that he______.
A.had found B.should find C.had lost D.should have found
26. It is natural that he______change his min D.
A.will B.should C.can D.ought to
27. What do you think of the proposal that we______a play at the English evening?
A.will put on B.must put on C.should put on D.can put on
28. It is about time you______the pills.
A.will take B.must take C.taken D.should take
29. It's high time we______.
A.started B.starting C.to start D.would start
30. I'm sorry that he______in such poor health.
A.would be B.should be C.will be D.shall be
31. Here's some money in case you______it.
A.needed B.needing C.should need D.to need
32. But for the storm,we______long go.
A.should have arrived B.will arrive C.arrive D.arrived
33. The old lady dresses as if it______winter even in summer.
A.will be B.would be C.is D.were
34. I will take a taxi;so that I______there in time.
A.got B.could get C.would get D.will get
35. I'd rather you______anything about it for the time being.
A.do B.don't C.didn't do D.didn't
36. How nice it______if you______a bit longer.
A.would be;could stay B.will be;could stay
C.will be;can stay D.would be;can stay
37. He______you more help,but he has been so busy.
A.has given B.would give C.will give D.could have given
38. I could go myself but I would sooner you______.
A.go B.went C.had gone D.has gone
39. ______tomorrow,he would get home before Wednesday.
A.Would he leave B.Was he leaving
C.If he leaves D.Were he to leave
40. Should it rain,the crops______.
A.would be saved B.would have been saved
C.will be saved D.had been saved
參考答案
1-10 DACDB ACDBA 11-20 CBCAD BCADB
21-30 CADBC ABDCA 31-40 CADBC ADBDA