语法结构虚拟语气

1、语法结构：虚拟语气虚拟语气是英语三级考试的必考知识点之一，也是体现英汉语言习惯区别的一个语法现象。在汉语里表示假设虚拟的情况常用一些虚词来表示，例如“假设”、“如果”等等；而英文中表示虚拟的情况不但有虚词的提示，谓语动词也要相应的变化。虚拟语气的基本作用是：1. 表达假设的情况，与事实相反；2. 表达异想天开很难实现的愿望；3. 表达建议、命令、劝告等语气。本节重在讲解if引导的虚拟条件句， 含蓄条件句，特殊结构中的虚拟语气，以及should+动词原形的用法。 一、虚拟语气的基本形式和用法虚拟(条件)语气中，主句与从句中谓语动词的形式可分为下面三类：假设类型条件从句谓语动词形式主句谓语动词形式

2、与现在事实相反If+动词的过去式(be用were而不用was)would(第一人称可用should)+动词原形与过去事实相反If+had+-ed分词would(第一人称可用should)+have+-ed分词与将来事实可能相反If+were to+动词原形或If+should+动词原形would(第一人称可用should)+动词原形下面我们列举近年的真题来强化记忆。例(1)Mary said to me, "Had I seen your bag, I _ it to you."A. will returnB. must returnC. could returnD. wo

3、uld have returned(【答案】D)(2004年4月45题)例(2)I would ask George to lend us the money if I _ him.A. had knownB. have knownC. knewD. know(【答案】C)(1995年38题)例(3)If Bob_ with us; he would have had a good time.A. would comeB. would have comeC. had comeD. came(【答案】C)(1995年59题)二、省略if的虚拟形式在虚拟条件句中，如谓语包含were，had，sho

4、uld等词，则可以把这些词放到主语前面，省略if。例(1)_ the advice of his friends, he would not have suffered such a heavy loss in his business.A. If he tookB. If he should takeC. Were he to takeD. Had he taken (【答案】D)(2004年4月32题)例(2)_, I should ask them some questions.A. Should they come to usB. If they come to usC. Were t

5、hey come to usD. Had they come to us(【答案】A)(1997年30题)例(3)_ you were busy, I wouldn't have bothered you with my questions.A. If I realizedB. Had I realizedC. Did I have realized thatD. As I realized(【答案】B)(1996年39题)三、含蓄条件句有时一个假设的情况不用条件从句表示，而用其它方式来表示，这样的句子叫含蓄条件句。常用with，without，but for。例(1)Without

6、heat and sunlight, plants on the earth _ well. A. would not growB. will not grow C. had not grownD. would not be grown (【答案】A)(2004年11月32题)例(2)But for my classmates' help, I _ the work in time.A. did not finishB. could not finishC. will not finishD. would not have finished (【答案】D)(2004年4月36题)例(3

7、)But for the rain, we _ a nice holiday.A. should haveB. would have hadC. would haveD. will have had(【答案】B)(2003年4月28题)四、特殊词或结构中的虚拟语气： 以wish(that)引导的表示“愿望”的宾语从句wish后的宾语从句中要用虚拟语气，而在虚拟语气中时态的应用类似在非真实条件中从句时态的应用。表示现在或将来的愿望用：主语wish 从句(主语过去时)；表示一个过去没有实现的愿望用：主语wish +从句(主语过去完成时)；例(1)I didnt go to the party, b

8、ut I do wish I _ there.A. wereB. would beC. had beenD. will be(【答案】C)(2001年53题)例(2)Peter wishes that he _ law instead of literature when he was in college.A. could studyB. studiedC. had studiedD. would study(【答案】C)(2000年53题) if only +句子(过去时/过去完成时)“要是就好了”If only 后面的句子如果是对现在或将来情况的虚拟，用过去时did ；如果是对过去情况的

9、虚拟，用过去完成时had done . 要注意与if 区别，if 只表示假设，“如果”，用真实语气；而if only 表示不可能实现的情况，用虚拟语气。例如：If only the alarm clock had rung. 当时闹钟响就好了。(对过去虚拟)If only I were rich. 要是我富有就好了。(对现在虚拟) would rather句子(过去时)表示宁愿、宁可的意愿，语气比较婉转。后接过去式。例(1)I am too busy these days. I would rather all of you _ next month for a dinner.A. comeB

10、. would comeC. came D. have come(【答案】C)(2002年46题)例(2)Id _ you didnt touch that, if you dont mind.A. rather B. better C. happierD. further(【答案】A)(1998年45题) it is time(that)，it is high time (that)句型中，谓语动词用过去时，表示早该做而未做的事，意思是该了、早该了.例(1)Let's finish our homework in a few seconds; it's time we _.A

11、. played footballB. will play footballC. play footballD. are playing football(【答案】A)(2004年11月43题)例(2)Dont you think it is time you _ smoking?A. give upB. gave upC. would give upD. should give up(【答案】B)(1999年31题) 以as if，as though引导的从句在as if，as though引导的从句中，如果谈论的是不可能或不真实的情况时，它们所引用的状语从句要用虚拟语气，动词形式和wish

12、后面的从句动词形式变化相同。例：He talks as if he _ everything in the world.A. knowsB. knewC. had knownD. would have known(【答案】B。本句表示说话人对现在的情况有所怀疑，所以用过去时。)五、should+动词原形及should的省略(1)、一些表示建议、要求、命令等的动词本身隐含说话者主观的意见。因此这些动词(或其变形，如名词，形容词，分词等)后面的从句应使用虚拟语气，即“should do”结构，其中的“should”常被省略。如：表“提议、建议”的动词：suggest ,advise, propos

13、e, recommend, move(提议);表“要求、主张”的动词：insist, require, request, demand , desire ;表“命令”的动词：order, command. 例(1)I dont think it advisable that Tom _ to the job since he has no experience.A. be assigned B. is assigned C. will be assigned D. has been assigned(【答案】A)(2006年11月29题)例(2)His mother insisted that

14、 he _ the coat when going out.A. put onB. puts onC. to putD. putting on(【答案】A)(1999年58题)此处省略了should.例(3)The doctor advised that Mr. Malan _ an operation right away so as to save his life.A. had B. would have C. have D. was going to have(【答案】C)(1998年28题)此处省略了should.(2)、It is necessary/important/essen

15、tial/ vital/urgent / surprising/ amazing that引导的主语从句中，从句的谓语动词要用should+原形动词，should也可以省略。此类形容词的特点是表示重要性或吃惊。例(1)it is vital that enough money_collected to get the project started. A. is B. be C must be D can be (【答案】B)(2004年11月24题)例(2)Its urgent that a meeting _ before the final decision is made.A. wil

16、l be arrangedB. must be arrangedC. be arrangedD. would be arranged(【答案】C)(2003年4月45题)(3)、以in case, lest, for fear that引起的状语从句，表示“以防，以免”。其形式为should+动词原形。如：He took his raincoat with him in case it should rain.他把雨衣带在身上以防下雨。1.3配套练习1. You didnt let me drive. If we _ in turn, you_ so tired.A. drove; didnt

17、 B. drove; wouldnt getC. were driving; wouldnt get D. had driven; wouldnt have got 2. _, we could not have finished the work on time.A. If they do not help us B. Was it not for their helpC. Should they offer to help us D. But for their help3. _ today, he would get there by Friday.A. Was he leaving B

18、. If he is leaving C. Were he to leave D. If he leaves 4. If only I _ how to operate a computer as you do!A. had known B. would know C. should know D. knew5. When a pencil is partly in a glass of water, it looks as if it _.A. breaks B. has broken C. were broken D. had been broken6. The chairman requ

19、ested that_A. the members studied the problem more carefullyB. the problems were more carefully studiedC. the problems could be studied with more careD. the members study the problem more carefully7. If I _ you, I _ more attention to English idioms and phrases.A. was; shall pay B. am; will payC. wou

20、ld be; would pay D. were; would pay8. We cannot imagine what our world _ like without electric power.A. is B. will be C. would be D. were9. There was a half smile on his face which suggested that he _ happy to have given his life for his country.A. was B. should be C. would be D. were10. We all agre

21、ed to her suggestion that we _ to the Great Wall for sightseeing.A. will go B. go C. shall go D. should have gone11. The young man insisted that he _ nothing wrong and _ free.A. did; set B. had done; should be set C. do; be set D. had done; must be set12. I lost your address, otherwise I _ you long

22、before.A. had visited B. have visitedC. would have visited D. should visit13._the rain we would have had a nice holiday.A. But thatB. But forC. DespiteD. In spite of14_no gravity, there would be no air around the earth.A. Were thereB. There wereC. Was thereD. There be15. Its getting rather late. Its time we_.A. are goingB. wentC. goD. must go16. They keep telling us that it is vital that we _there on time.A. areB. beC. must beD. would be答案与解析1. 本句是对过去情况的虚拟。意为：如果我们轮流开车的话，你就不会那么累了。对过去虚拟，if条件句用过去完成式，had driven，主句用wouldnt have got。选D2. 选D。 这里是含蓄虚拟语气用法。这句话的意思是：要不是他们帮忙，我们不会按时完成工作的。3. 选C。这是考