大学英语语法-虚拟语气讲课稿

虚拟语气1. I wish (that可省略,下同)I knew the answer to the question.我希望知道这个答案。

(事实上是不知道)2. He wishes he hadn't lost the chance.他真希望没有失去机会。

(其实已失去)3. You wished she would arrive the next day.(would + arrive)你希望她第二天会到。

(事实上她还没到)Subjunctive Mood作为专门表达假设意义和其他非事实意义的动词形式，仅是古英语遗留下来的残余。

它仅有两个形式，即be型虚拟式和were型虚拟式。

Be型虚拟]-----be型虚拟式是以动词原形表示的，不管主语是什么人称，动词一律用原形，如动词为被动态，则助动词be也用原形。

其主要用法如下：1)用于表命令、决定、建议、坚持等词语之后的that分句中这一用法又分三种情况：a)用在decide,decree,demand,insist,move,order,prefer,propose,recommend,request,require, suggest,vote等动词之后的that分句中.（宾语从句）在expect, believe, think, suspect等动词的否定或疑问形式后的宾语从句中，我们经常用“should＋动词原形(或完成形式)”，表示惊奇，怀疑，不满等。

He ordered that all the books be sent at once.He ordered that all the books be sent at once.we propose that somebody neutral take the chair.She insisted that she go to the south for her holiday.b)用在advisable,appropriate,desirable,essential,fitting,imperative,important,impossible,nece ssary,obligatory,proper等形容词之后的that分句中。

（主语从句）It is essential that all the facts be examined first.It was appropriate that thisi tax be abolished.I thousht it advisable that an armed guard stand in readiness.c)用在decision,decree,demand,instruction,order,requirement,resolution等名词之后的that分句中。

The board has given instructions that the agent fly to Boston.We were faced with the demand that this tax be abolished.Their decision was that the school remain closed.在这一用法中be型虚拟式能与“should+不定式”交替使用，也能与to-不定式交替使用。

He ordered that the books be sent at once .= He ordered that the books should be sent at onc.= He ordered that the books to be sent at once.2）用于由if,though等引导的分句中.be型虚拟式能用于由if,though,whatever,lest,so long as lest, for fear that, in caseso that, in order that 等引导的分句中表推测、让步、防备等含义。

If he be found guilty,Jonh shall have the right of appeal.Though everyone desert you, I will not.Quitly we sat on the river bank lest the fish swim away.上述用法现在只限于书面体，在非正式语体中通常用动词陈述式或者用should/may+不定式。

Whatever hisdefense maybe,we can’t tolerate this disloyalty.3）用于某些公式化语句中be型虚拟式用于某些公式化语句中可表祝愿、诅咒、禁止等意义。

Long live the People's Republic of China!God bless you!God damn you!So be it.(但愿如此吧)Were型虚拟]-----Were 型虚拟语气只有一种形式，即无论主语是什么人称，动词一律用were，如I were，you were ，如果动词为进行体或被动态，其助动词也一律用were，如I were going，you were going，I were sent ，you were sent1）用于某些状语从句如if , if only, as if , as though, though引导的条件状语和让步状语从句，表示非真是的条件或让步。

If I were you, I should wait till next week.If only I were not so nervous.He behaves as though he were better than us.2）用于某些名词性从句如wish, would rather, suppose,imagine 之后的that—分句中，表示一种臆想的(通常是不可能发生的事)I wish it were spring all the year round.I’d rather I were not at the site of the accident.Suppose the earth were flat.上述were型虚拟式在第一三人称单数主语之后可为was 所取代。

If it was to rain,the game would be put off.If only I was not so nervous.但是，在if I were you 这一分句中，通常不用was 。

另外在某些倒装句结构中只用were，不用was。

Were I to do it =（if I were to do it），I should rely on you.还有在as it were（作so to speak 解，即“宛如””好比”）结构中也只用were，不用was He is my best friend，my second felf ,as it were.假设意义表示法综述1）用动词的过去时形式表示假设意义a) It is (high ,about )time thatIt is time that we went (或should go) to bed.It’s about time that we put an end to this controversy.b) I would rather / would sooner / would as soon / would just as soon (that) you / he/ theyI’d sooner she left the heavy end of t he work to someone else.c) if onlyIf only I knew what you wanted.If only he had arrived in time,he would not have been punished.d) as if, as thoughIt seems as if it were spring.现在好像是春天似的。

She appeared as if she had known nothing about it.她看上去对此一无所知。

as if, as though结构中如果不表示假设意义，就不必用过去时时态。

It looks as if it is going to rain.e) I wish(that)I wish I remembered the address.I wish 与I hope都表示“希望”但I hope 并不表示假设意义其后很少用过去时时态。

I hope you are ready.用情态助动词过去时时态表示假设意义最常见于条件句和含蓄条件句a）用于条件句（若if 省略要用到装）If she were younger, she would do it.去If：Were she younger, she would do it. (把动词were移到主语she的前面)If he had tried it, he could have done it.去If：Had he tried it, he could have done it.(把had移到主语he的前面)Were I a bird, I could fly freely.如果虚拟条件句中有were, had或should时，把它们放在if的位置上；但是如果条件句中没有were, had或should不能用倒装。

如：Should it rain tomorrow, what should we do?要是明天下雨的话，我们怎么办呢？Were I you, I would have asked him for some advice.要是我是你的话，我就向他请教了。

在“开放式条件句”(open conditional clause)和让步状语从句中若should是被省略了的。

在这种情况下，如果if省略，动词be与主语的位置要倒装。

如：If any person be guilty of a crime, the court shall have the right to appeal. (任何人犯罪，法院有权起诉。

)Be any person guilty of a crime, the court shall have the right to appeal.Whether she be right or wrong, she will have my unanswering support. (不管她对与错，我都会支持她)Be she right or wrong, she will have my unanswering support.注意：有时虚拟条件句并没来if 从句表示出来，而是用介词短语(otherwise, or, without, but for)、上下文或其它方式来表示。