英语语法之虚拟语气
虚拟语气
情态动词所表达的可能性程度：must/can't should/shouldn't might/may (not)
另外两个"类情态词的形式："need/needn't; haveto/don't have to 最自然的虚拟状态：由should/would+原型时态（不含时间只含状态）本质上是过去将来时：即，时间固定在过去将来，状态不同：一般、进行、完成、完成进行。
这时"虚拟语气"的产生往往是因为我们要表达"本来应该……"（而现在却还没有……）
（本来可以……，本来能……）
I should go! (… but I'mstill here!) (一般)
I should be working now! (进行)
I should have practiced more (than I did)! (完成)
我应该多多练习！（言下之意，现在我练习得不多。）
I shouldn't dream away my time too much! (完成的否定)
(actually I did dream away my time toomuch!)
It shouldn't have been leaking for such along time! (完成进行)
I may/might/could have finished! (完成)
一些常见的句型中，就会出现这种虚拟语气，而处于从句之中，should 常常被省略掉
suggest,advise, propose, recommend, plan;
demand,order, direct, arrange, command, decide;
require,request;
think,expect, believe, insist, suspect.
由于他们的含义中包含"建议，假设，应该"这类的含义，所以，由他们引起的从句中，就会包含有should+原型时态构成的虚拟语气。这些动词（以及他们的名次形式，分词形式）引起的从句还有其他的变形：主语从句，表语从句，同位语从句
It's suggested that…
My suggestion is that…
The only suggestion that...
The only suggestion I can give you now isthat…
一些形容词引起的表语从句中，也会有同样的情况
important;necessary; essential
It's natural ; strange; incredible
apity; a shame; no wonder
由lest, forfear that, in case 引起的从句中多使用should表达与事实相反
1. 与现在相反：使用[过去时]：
Iwish I were not here! (一般现在à一般过去)
Suppose we were not here.
Heloved me as if I were his own son. (一般现在à一般过去)
HopeI weren't always losing things! (现在进行à过去进行)
Ifonly/If I hadn't been there! (现在完成à过去完成)
Whatif I hadn't been waiting right here! (现在完成进行à过去完成进行)
常考句型：It's(high) time (that)…; would rather (that)…
这两个从句，只能表达对现在的看法，所以，从句中只有一般过去时。
2. 与过去相反：过去完成时；
How nice it is if I had past the test!
How nice it is if I had slept a little more this morning!
3. 与将来相反？将来的事情没有发生，所以只能推测。
If it rains tomorrow, we'll have to stay one day more.
不过，由于可以用be to表示将来；所以，虚拟语气中经常出现were to；也CET-4的常考语法点。
虚拟条件句
if 部分，做一个与事实相反的假设（所以只有一般过去和过去完成）；
主句部分,这是表示基于这个假设的推测，一般使用情态动词would，少数情况下使用could/might/may。
注意：两个部分之间,是有逻辑关系，而在两部分的谓语动词时态上，没有必然的联系。
注意，虚拟条件句中的if可以省略，造成were/had提前，产生倒装。
隐含的非真实条件
What would you do with 50 thousand dollar?
How could I be happy without you?
除了条件状语从句之外，原因状语从句也会出现虚拟语气。
常考知识点：
1 虚拟语气在条件状语从句中的应用
(1)表示与现在的情况相反，或将来实现的可能性很小，if从句用过去式（动词be多用were这个形式），主句用“would／should／could／might＋动词原形”。例如：
If places alike, there would be little needfor geographers.
A. being B. are C. be D. were
如果各地方都一样，就不需要地理学家了。（1991.6.-4, 答案是Ｄ）。
在表示将来情况的虚拟条件句中，还可以用“were＋to 不定式”或“should＋动词原形”。
Jean doesn't want to work right awaybecause she thinks that if she ____ a job, she probably wouldn't be able to seeher friends very often.
A) has to get B) were to get
C) had got D) could have got
吉不想立刻工作，因为她想：如果她得到一份工作，她就不能经常去看她的朋友了。(96.1-44, B对）
If it should rain tomorrow, we should haveto put off the picnic.
万一明天下雨，我们只好推迟野餐。
(2) 表示与过去的事实相反，从句用过去完成时，主句用“would／should／could／might＋have＋过去分词”。如:
If the policeman had arrived earlier, hewould have seen the accident.
要是警察更早些到达，他就能见到事故了。
Ifbetter material had been used, the efficiency of the machine would have beenmuch increased.
如果使用更好的材料，机器的效率会大大提高。
(3) 注意如果以上两类条件句中含有助动词、情态动词，be或have, 则常常不用if，而用倒装结构：
My cat wouldn't have bitten the toy fish itwas made of rubber.
A) if she has known B) if she knew
C) she should have know D) had she known
如果我那只猫知道那条玩具鱼是用橡胶制作的，她就不会去咬它了。 (1988.6, 答案是D）
____ for my illness I would have lent him ahelping hand.
A) Not being B) Had it not been
C. Without being D) Not having been
如果不是我病了,我本来是会帮助他的。（95.1-47, B对)
____ before we depart the day aftertomorrow, we should have a wonderful dinner party.
A) Had they arrived B) Would they arrive
C) Were they arriving D) Were they toarrive
如果我们后天走之前他们到达的话，我们就举行一次丰盛的宴会。 (97.1-34, D对）
____ right now, she would get there onSunday.
A) Would she leave B) If she leave
C) Were she to leave C) If she had left
如果她立刻就走,她就能在星期天到达那里。(96.6-42, C对)
Had he worked harder, he ____ the exams.
A) must have got through B) would have gotthrough
C) would get though D) could get through
如果他学习更努力些，本来是可以通过考试的。(97.6-42, B对)
(4) 有时候条件并没有用if从句表示出来：
We didn't know his telephone number,otherwise we ____ him.
A) would have telephoned B) must havetelephoned
C) would telephone D) had telephoned
我们不知道他的电话号码；要是知道的话，我们早就打电话给他了。(95.6-46, A对）
(5) 有时候，条件句表示的动作，与主句表示的动作，发生的时间不一致（如一个发生在过去，一个发生在现在），这时，动词的形式要根据表示的时间来调整：
If I hadn't stood under the ladder to catchyou when you fell , you ____ now.
A) wouldn't be smiling B) couldn't havesmiled
C) won't smile D) didn't smile
你掉下来的时候，如果我没有站在梯子下面看着你，你现在就不会笑了。 (99.1-60, A对。这种句子语法家称为错综时间条件句)
2 表示命令、建议、要求的动词之后的宾语从句
在表示命令、建议、要求的动词(如move, intend, order, request,suggest, propose, command , desire, prefer, insist）之后的宾语从句，或名词（如suggestion, motionproposal, order, recommendation）之后的表语从句和同位语从句，以及it is desired, it is suggested, it is ordered 等结构之后的主语从句，谓语用动词原形或“should＋动词原形”，前者在新闻文字、外交文件、提案及口语中更为常见，美国人也较爱用前一种形式。注意这种句型中的虚拟语气形式不受主句动词时态的影响。如：
Our teacher recommends that we _____ asattentive as possible when visit the museum.
A. are B. shall C. were D. be
老师劝我们在参观博物馆时尽可能地聚精会神。 ( 88-4 答案是D)
We desire that the tour leader usimmediately of any change in plans.
A. inform B. informs C. informed D. hasinformed
如果计划有变动，希望导游立即通知我们。（ 93.6-48, 答案是A）
He suggested to tomorrow's exhibitiontogether.
A. us go B. we went C. we shall D. we go
他建议我们明天一起去参观展览。（89.1-4，答案是Ｄ）
My father didn't go to New York, the doctor suggested that he ____there.
A. not to go B. not go
B. C. hadn't gone D. wouldn’t go
我父亲没去纽约，医生建议他不要去那儿。(93.6-4, 答案是B)
We are all for your proposal that thediscussion ____.
A) be put off B) was put off
C) should put off D) is to put off
我们都赞成你的建议，把讨论推迟。(98.6-68,A对)
It was proposed that the matter discussedat the next meeting.
A. will be B. was C. would D. be
有人建议这个问题在下一次会议上讨论。（92.6-4. 答案是Ｄ）
It is recommended that the project ____until all the preparations have been made.
A) is not started B) will not be started
C) not be started D) is not to be started
有人提议：让所有的准备工作做好后该工程才动工。(95.6-44, C对)
3 在important等形容词之后的that从句
在important, vital, essential,necessary, strange , incredible，advisable, preferable, urgent 等形容词之后的that从句，谓语用动词原形或“should＋动词原形”：
It was essential that the application formsback before the deadline.
A. must be sent B. would be sent
C. be sent D. were sent
申请表务请在截止日期前送回。（1990.1 答案是Ｃ)
It is necessary the dictionary immediately.
A. that he will return B. that he returned
C. that he return D. that he had to return
他必须立即还那本词典。（1992.12答案是C）
I don't think it advisable that Tim ___ tothe job since he has no experience.
A) in assigned B) will be assigned
C) be assigned D) has been assigned
我认为把这工作分配给Tim是不明智的，因为他没有经验。(97.6-55, C对)
It is vital that enough money ____ to fundthe subject.
A) be collected B) must be collected
C) is collected D) can be collected
筹集足够的钱为该项目提供资金，这点至关重要。(97.1-45, A对)
4 would rather, would sooner 也用来表达主观愿望，它们之后的宾语从句，谓语用过去式
would rather, would sooner 也用来表达主观愿望，它们之后的宾语从句，谓语用过去式：
I'd rather you those important documentswith you.
A. didn't take B. won't take
C. didn't take D. not take
我宁愿你身上不带那些重要文件。(93.6,答案是C)
I'd sooner you didn't hurt Jim so much. Heis still very depressed.
吉姆还很沮丧，你就不要那样伤他的心了。
To be frank, I'd rather you ____ in thecase.
A) will not be involved B. not involved
c) not to be involved D. were not involved
坦诚地说,我宁愿你不要卷入这个案子。(95.1-61，D对)
You don't have to be in such a hurry, Iwould rather you ___on business first.
A) would go B) will go
C) went D) have gone
你不必如此匆忙，我宁愿你先做生意。(98.1-59, C对)
I'd rather you ___ make any comment on theissue for the time being。
A) don't B) wouldn't C) didn't D) shouldn't
我宁愿你对这个问题暂时不要发表意见。(98.6-48, C对)
Frankly speaking, I'd rather you ____anything about it for the time being.
A) didn't do B) haven't done
C) don't do D) have done
坦诚地说，关于这，我宁愿你目前不要做任何事情。(99.1-66, A对)
5 在wish之后的宾语从句，ifonly 引起的状语从句中，谓语动词要用虚拟语气
在wish之后的宾语从句，if only 引起的状语从句中，谓语动词要用虚拟语气。如：
He didn't go to the party, but he does wishhe there.
A) had been B) has been
C) would have been D) would be
他没有去参加聚会，但他的确希望他去了那里。（1992.6 答案是Ａ)
I wish I ___ longer this morning, but I hadto get up and come to class.
A) could have slept B) slept
C) might have slept D) have slept
今天早上我能睡得更久些就好了，可惜我得起床去上课。(95.6-45,A对)
Look at the situation I'm in! If only I ___your advice.
A) follow B) had followed
C) would follow D) have followed
瞧！我的处境多么糟糕，要是我听了你的忠告就好了。(1993.6 答案是B)
If only the committee ____ the regulationsand put them into effect as soon as possible.
A) approve B) will approve
C) can approve D) would approve
要是委员会能通过这些规定并使之尽快生效就好了。（97.1-47, D对）
6 在it is（high） time 之后的定语从句，谓语用过去式
在it is（high） time 之后的定语从句，谓语用过去式：
It's time about the traffic problemdowntown.
A) something was done B) anything will bedone
C) everything is done D) nothing to be done
该是采取一些措施解决市区交通问题的时候了。 （1993.6 , 答案是Ａ）
It's already 5 o'clock now. Don't you thinkit's about time ____?
A) we are going home B) If she leaves
C) we went home D) If she had left
现在已经 5 点钟了,你难道不认为该回家了吗? ( 96.6-43, C对)
“You are veryselfish. It's high time you ______ that you are not the most important personin the world.” Edgar said to his boss angrily.
A) realized B) have realized
C)realize D)should realize
“你真自私！你早该清醒了，你并不是世界上最重要的人物。”伊葛愤怒地对老板说。(99.1-57, A对)
7 在as if引导的状语从句中，谓语可用虚拟语气，也可用陈述语气，要看句子的意义而定
在as if引导的状语从句中，谓语可用虚拟语气，也可用陈述语气，要看句子的意义而定。如：
That tree looked as if it for a long time.
A) hasn't watered B) didn't water
C) hadn't been watered D) wasn't watered
（1992.12 答案是Ｃ）那棵树看上去好像很久没人给它浇水了。（虚拟语气）
It looks as if it is going to rain.
好象要下雨了。（陈述语气）
8 在lest 引导的状语从句中，谓语动词用陈述语气或虚拟语气
在lest 引导的状语从句中，谓语动词用陈述语气或虚拟语气（“should＋动词原形”或动词原形）
I asked them to ring first lest we wereout.
我请他们先打电话来，以免我们不在家。（陈述语气）
Themad man was put in the soft-padded cell lest he ______himself.
A) injure B) had injured
C) injured D) would injure
这个疯子被关进墙上装有衬垫的病房，以免伤了他自己。(98.1-38, Ａ对。虚拟语气）
9 不定式的完成式用在某些含有“希望、打算、期望”等意义的动词的过去式之后，表示希望做的事没有做
不定式的完成式用在某些含有“希望、打算、期望”等意义的动词的过去式之后，表示希望做的事没有做。这些动词包括expect, hope, intend, mean, promise, think, want, wish与should/would like等。例如：
I meant to have written to you as soon as Igot there, but I was too busy to do so.
我原想一到那儿就给你写信，但我太忙了，就没有写。
这些动词的过去完成式后接不定式的一般式也表达同样的意思:
I had meant to write to you as soon as Igot there, but I was too busy to do so.
We ____ to start our own business, but wenever had enough money.
A) have hoped B) would hope
C)had hoped D) should hope
我们原想开办自己的企业,可是钱不够。（94.1-46, C对)
