专四语法考点解析之虚拟语气
语法是语言学的一个分支，研究按确定用法来运用的"词类"、"词"的屈折变化或表示相互关系的其他手段以及词在句中的功能和关系。下面是小编给大家带来专四语法考点解析之虚拟语气，希望能给大家带来帮助。
考点一：表示建议、要求、命令等动词如insist, order, command, suggest, advise, propose, ask, require, request, demand引导的从句及it引导的相应的分词、名词和形容词从句，谓语用(should)+动词原形。
1. It was recommended that passengers _not __ smoke during the flight.(2004/1994)
A. not B. need not C. could not D. would not
2. He left orders that nothing _should be_____touched until the police arrived here.1997
A. should be B. ought to be C. must be D. would be
3. She asked that she __be____ allowed to see her son in police custody. 1993
A.would be B.could be C.be D.was
4. The teacher demanded _that Tom hand in_____ his essay immediately.1991
A. Tom to hand in B. that Tom hands in C. that Tom handed in D. that Tom hand in
考点二：It is +advisable, essential, important, imperative, incredible等从句，谓语用(should)+动词原形。
1. It is necessary that he _hand in___ the assignment without delay.2010
A. hand in B. hands in C. must hand in D. has to hand in
2. It is absolutely essential that William _continue___ his study in spite of some learning difficulties.2007
A. will continue B. continued C. continue D. continues
3. It is imperative that the government _attract_ more investment into the shipbuilding industry.2006
A. attracts B. shall attract C. attract D. has to
4.It is imperative that students _hand in___ their term papers on time.2004?
A. hand in B. would hand in ?C. have to hand in D. handed in?
5. The opening ceremony is a great occasion. It is essential _for us to be prepared____for that.2003
A. for us to be prepared B. that we are prepared C. of us to be prepared D. our being prepared
考点三：If从句中的虚拟语气
省略if，从句的语序用到装，即将were,had或 should移至主语的前面，但否定词not不前移。
(一)与过去事实相反：从句sb had done，主句sb would(should,could,might)+ have done;
1. Had Judy been more careful on the maths exam, she _could have got___ much betterresults now.2008
A. would be getting B. could have got C. must get D. would get
2. He would have finished his college education, but he _had___to quit and find a job to support his family.2007
A. had had B. has C. had D. would have
3._Had he not been taken good care of __, he would not have recovered so quickly.2005/1995
A. Hadn't he been taken good care of B. Had he not been taken good care of
C. Had not he been taken good care of D. Had he been not taken good care of
4. I _would have enjoyed__the party much more if there hadn’t been quite such a crowd of people there.2004/1996
A. would enjoy B. will have enjoyed C. would have enjoyed D. will be enjoying
5. All of us would have enjoyed the party much more if there _had not been__ quite such a crowd of people there.2004/2000
A. weren’t B. hasn’t been C. hadn’t been D. wouldn’t
6. _Had it not been__for the fact that she broke her leg, she might have passed the exam.2002
A. Had it not been B. Hadn’t it been C. Was it not D. Were it not
7. _Given____enough time and money, the researchers would have been able to discover more in this field.1998
a. Giving b. To give c. Given d. Being given
8. I was to have made a speech if_I had not been called away__.1997
A. I was not called away B. nobody would have called me away
C. I had not been called away D. nobody called me away
9. __Given___ time, he’ll make a first-class tennis player. 1996
A. Having B. Given C. Giving D. Had
10. We could _have provided__him with a detached house when he came, but he had specifically asked for a small flat.1995
A. provide B. have provided C. not provide D. not have provided
11. _Had I realized_____you were busy, I wouldn’t have bothered you with my questions. 1994
A. If I realized B. Had I realized C. I realized that D. As I realized
12. _Had it not been for____ their help, we would not have succeeded.1992
A. Hadn't been for B. Had it not been for C. It hadn't been for D. Had not it been for
13. If you _had not been____ in such a hurry you would not have put sugar into the sauce instead of salt.1992
A. were not, would not put B. were, would put
C. had been, would have put D. had not been, would not have put
14. "Did you hear of his death?'
"Yes. If he _had been operated on__ in time, hemight not have died___.”1990