英语虚拟语气讲解

虚拟语气
虚拟语气(Subjunctive Mood)这一语法项目是各类英语考试中心测试的重点之一。

虚拟语气是一种特殊的形式，用来表示说话人所说的话
并非是事实，而是一种假设、愿望、疑心或推测。

Ⅰ用以表示虚拟条件的虚拟语气
虚拟条件句的三种大体类型:
1.与此刻事实相反。

假设与此刻事实相反，条件从句的谓语用过去式(be通经常使用were)，主句谓语用“should (would, could, might)+动词原形”：If you took a taxi，you’d get there quicker. 若是你坐出租车去，你能够快一点到那里。

(但你不坐)
If I knew her number I could ring her up. 若是我明白她的号码，我就能够够给她打了。

(可惜我不明白)
2.与过去事实相反。

假设与过去事实相反，条件从句的谓语用过去完成时(had+过去分词)，主句谓语用“should (would, could, might)+have+过去分词”：If I’d left sooner，I’d have been on time.若是我早点起身，我就准时到了。

(但我起身太迟了)
If we had found him earlier we could have saved his life. 若是咱们那时早点找到他的话，咱们就能够够救活他。

(可惜咱们找到他太晚了)
3.与以后事实相反。

假设与以后事实相反，条件从句的谓语用过去式(be通经常使
用were)，主句谓语用“should (would, could, might)+动词原形”：If he went，would you go too? 若是他去，你也去吗?(可能他可不能去) If I asked him，I’m sure he’d help us. 若是我向他提出要求，确信他会帮忙咱们。

(只是我不打算如此做)
大多数的虚拟条件句属于上面三种情形的一种，但并非排除存在条件和
后果中，一个和此刻情形相反，另一个和过去情形相反，例如：If you had followed what the doctor said, you would not have been so painful now.那个句子在高中显现频率颇高。

可是，若是后果用了虚拟语气，而条件却用陈述语气，这种用法是错的。

2. 除表示虚假条件外，if从句还能够表示对以后的推测，由于是以后
尚未发生的，因此谈不上是真实的仍是虚假的，只能说那个情形发生的
可能性有多大。

一样情形下，能够用陈述语气的if从句来表示对一个以
后事实的推测，那个事实是完全可能发生的。

If从句的谓语形式用一样过去式或用were to / should +动词原形，主句用would / should /could/ might +动词原形，例如：Jean doesn't want to work right away
because she thinks that if she were to get a job she probably
wouldn't be able to see her friends very often.（1996年1月四级第44题）
3. 有时能够把含有助动词、、be或have的虚拟条件句中的if 省去，而将had , should, were 等词提到主语之前，即用倒装结构,这时，若是显现not等否定词，否定词需放在主语后面。

这种结构在口语中很少利用，但几回出此刻各类考试中显现，例如：If it had not rained so hard yesterday we could have played tennis.→Had it not rained so hard yesterday, we could have played tennis.
4. 大多数的虚拟条件通过上面所讲的两种方式表达，但在个别句子中也能够通过without和介词短语but for表达，otherwise等表达出来。

例如：We didn't know his telephone number; otherwise we would have telephoned him.（1995年6月四级第46题）值得注意的是，包括but for的句子，谓语动词必然要用虚拟形式，但包括without等短语的句子，谓语动词未必必然要用虚拟语气。

5. 有时虚拟条件不是明确地表达出来，而在包括在用but引导的从句里，于是便显现了有谓语动词是虚拟语气的主句加上谓语动词是陈述语气的but从句组成的并列复合句，例如I would have hung you but the telephone was out of order.在如此的句子里，若是主句没有效虚拟语气，或从句用了虚拟语气，都是错的。

Ⅱ用在中的虚拟语气
1.用wish的虚拟语气：
虚拟语气通经常使用于wish后的宾语从句中，表示与事实相反或不大可能实现的愿望。

通常有三种形式：
①对以后发生的情形表示祝愿或愿望：主语＋wish＋从句主语＋would(could, might)+动词原形
eg：I wish she would try again.
我希望她能再试一次
②表示与此刻事实相反的愿望：主语＋wish（that）＋从句主语＋动词过去式
eg：I wish I wasn’t leavin g my son.
我希望我没离开我儿子.
③对过去发生的情形表示遗憾或后悔时：主语＋wish（that）＋从句主语＋would/could have/had＋过去分词
eg：I wish you had come to my birthday party.
你若是来了我的生日晚会就好了。

* 从句的时态只与从句所指的时刻有关，与wish的时态无关。

2. 在具有愿望、请求、建议、命令等主观意愿的动词(desire, demand,
advice, insist, require, suggest, propose, order, recommend,
decide …) 后的宾语从句中需用虚拟语气。

谓语动词用(should) +动词
原形。

值得注意的是，若是宾语从句的动词是不是定的，否定词not的
位置应在动词之前，而不是动词以后。

例如：The head nurse insisted that the patient not be move.另外，如suggest表达“暗示”，insist 表示“坚持某种说法”时，后面的从句不用虚拟语气，例如：Her pale face suggests that she is ill.或He insisted that he did not kill the boy.
①在It is+上述动词的过去分词，其后所跟的主语从句中，如It is suggested that pupils wear school uniforms.
②在上述动词相应的形式作主语+，其后的表语从句中，例如His suggestion was that classed be re-scheduled.
③在对上述动词相应的名词进行说明的中，如：The workers raised the demand that their pay be increased to cope with the inflation.
3. would （had）rather , would sooner也用来表达主观愿望，它们以后的宾语从句中需用虚拟语气。

谓语动词用过去式表示此刻或以后，用过去完成式表示与过去事实相反，例如：I would rather he went right now.
Ⅲ含蓄虚拟语气
所谓含蓄虚拟语气,确实是句子里不显现明显的假设条件从句,但假想的条件隐含在上下文逻辑关系中,或通过一些语法手腕得以表现,这种情形就称为含蓄虚拟语气.
--含蓄条件暗含在其他结构中.
(1)连词but（可是）,or (else) (不然）；副词otherwise（不然）,unfortunately
等表示转折假设.
如：
A safety analysis would have identified the target as a potential
danger.Unfortunately,it was never done.
Victor obviously does not know what has happened; otherwise he wouldn't have made such a stupid remark.
(2)介词短语暗含假设条件,经常使用的有：without（假设没有），but for / but that
（要不是因为）,except for（假设没有）,with（假设带有）,under more favorable conditions,in the absence of（在没有……的情形下）,under the circumstances of（在……的情形下）等.
如：
But for the English examination I would have gone to the concert last
Sunday.
(3)intended/meant/hoped/wished/plann或was/were +不定式完成式或had
intended/meant/planned/hoped/wished +不定式一样式暗示虚拟语气.
如：I intended to have called on you,but I was busy at that time.（事实上我没打）
(4)情态动词完成式暗示虚拟语气.
如：I should have called to make an airline reservation.(事实上我没有）
Ⅳ虚拟语气的倒装
当虚拟条件句的谓语部份含有were, should, had时，咱们能够将连词if省略掉，而将were, should, had置于句首。

如：
If she were in charge, she would do things differently.=Were she in charge, she would do things differently. 若是是她负责，她会是另一种做法。

If you should change your mind, no one would blame you.=Should you change your mind, no one would blame you. 万一你改变主意，谁也可不能怨你。

If the management had acted sooner, the strike wouldn’t have happened.= Had the management acted sooner, the strike wouldn’t have happened. 若是资方早些采取行动，就可不能发生罢工了。

几点说明：
1. 关于条件从句含有should而主句利用陈述语气或祈使语气的句子也能够采纳以上方式进行省略和倒装。

如：
If I should be free tomorrow, I will come. = Should I be free tomorrow, I will come. 若是明天我有空我就来。

If they should attack us, we’ll wipe them out completely.=Should they attack us, we’ll wipe them out completely. 假设他们进攻咱们，咱们就把他们完全消灭干净。

有时被提到句首的had不是助动词，而是表示“有”的实义动词。

如：
Had I the time, I would go. 如有时刻我就去。

2. 若是条件从句为否定式，注意要将not置于主语以后，而不置于主语之前。

如：
假设非你的帮忙，我仍会无家可归。

误：Weren’t it for your help, I would still be homeless.
正：Were it not for your help, I would still be homeless.
要不是我亲眼所见，我都可不能相信了。

误：Hadn’t I seen it with my own eyes, I would not have believed it.
正：Had I not seen it with my own eyes, I would not have believed it.
Ⅴ虚拟语气的省略
1. 在表示建议,要求,命令,方式的动词后的从句里, 用should + 动词原形,
should 能够省略. 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,方式的名词后的从句里, 用should + 动词原形,
should能够省略. 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 从句顶用should的结构, should 能够省略. 这种形容词常见的有: 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(以避免),in case(以防)从句顶用should, should 能够省略.
She walked quietly lest she (should) wake up her roommates.
Have your gun ready in case we should need it.
Ⅲ其他形式的虚拟语气
1. it is +necessary等后，that主语从句中虚拟形式利用，这种形容词包括necessary, important, essential, imperative, urgent,
preferable, vital, advisable等，例如It is necessary that you listen to the teacher carefully.或It is essential that you be able to pronounce every single word correctly.（此句中省略should，故用be）
2. 在It's (high/about) time 以后的中需用虚拟语气。

谓语动词用过去式，例如It is high time that you went to school
3. 虚拟语气在as if / as though 引导的方式中的应用（谓语动词形式与wish后的宾语从句大体相同）表示与此刻事实相反或对此刻情形有疑心，谓语动词用过去式。

例如：He felt as if he alone were responsible for what had happened. 表示过去想象中的动作或情形，谓语动词用过去完成式。

4. 在lest 引导的状语从句中，谓语动词多用虚拟语气，(should )+ 动词原形。

例如：The mad man was put in the soft-padded cell lest he injure himself.（1998年1月四级第38题）
5. 在if only 引发的中需用虚拟语气。

谓语动词用过去式或过去完成式。

例如：Look at the terrible situation I am in! if only I had followed your advice.。