虚拟语气的主句,从句都指什么?结构?再加上一些习题,最好备有答案及讲解,

虚拟语气的主句,从句都指什么?结构?再加上一些习题,最好备有答案及讲解,
虚拟语气的主句,从句都指什么?结构?再加上一些习题,最好备有答案及讲解,

虚拟语气的主句,从句都指什么?结构?再加上一些习题,最好备有答案及讲解,
虚拟语气是以动词的特殊形式来说明句中所叙述的内容不是事实,或是不可能发生的事情,而是一种愿望、建议或是与事实相反的一种假设.虚拟语气通常出现在各种主从复合句中.
一、在宾语从句中
1．当主句的谓语动词为“suggest,propose,advise,insist,order,demand,require,request, desire’’等表示“建议”、“命令”、“请求”和“要求”的动词时,其后的宾语从句中要用虚拟语气“should+动词原形”(在美国英语中 should省略).例如：
I suggest that we(should)hold a meeting tonight．我建议我们今晚开个会.
We advise that steps(should)be taken at once．我们建议要立刻采取措施.
They insisted that he(should)begin the work at once．他们坚持让他立刻开始工作.
He ordered that aU(should)take part in the work．他下令所有的人都要参加这项工作.
另外,当主句动词为“ask,move,urse”等意为 “要求”、 “提议”和“极力主张”时,其宾语从句也常用虚拟语气.例如：
He asked that he be given an opportunity to try．他要求给他一个尝试的机会.
I move that the money be used for books． 我提议把这笔钱用于买书.
They urged that we take action on this matter immediately．他们极力主张我们对这件事立即采取行动.
2．当主句动词为wish,表示“但愿……”,“要是……该多好叼”之意时,其后的宾语从句有以下三种虚拟语气形式.
①动词用过去式来说明与现在的事实相反(BE动词常用were,但有时也可用was).例如：
1 wish 1 were／Was as strong as you．我要是像你一样强壮就好了.
1 wish l remembered his address．我要是记住他的地址就好了.
有时；为了强调现在状态下能发生某种情况或进行某项动作,从句中的动词也可用过去进行式.例如：
1 wish it wasn’t raining．要是天不下雨就好
了.
②动词用过去完成式说明与过去的事实相反.例如：
We wish we had paid more attention to our pronunciation．我们以前要是能更注意我们的发音就好了.
He wished he had stayed at home.他但愿他呆在了家里.
③情态动词“would,could,might”等后接动词原形,表示对将来的希望(通常不用should).例如：
1 wish he would try again．我希望他再试一下.
We wish he could come．我们希望他能来.
3．在prefer之后的宾语从句中用“should+动词原形”(should可省略).例如：
We prefer that the plan(should)be fully discussed before being put into execution．我们希望在计划实施之前进行认真的讨论.
4．在would rather之后的宾语从句中,其动词用虚拟语气,表示句子的主语(某人)宁愿让另一人做某事.
①用动词过去式表示现在或将来要做的事.例如：
I’d rather you went home now．我宁愿让你现在就回家.
Don’t come tomorrow．I’d rather you came nextweekend．明天别来,我宁愿你下个周末来.
一Shall l open a window?我开窗行吗? 一I’d rather you didn’t．你最好别开.
②用动词的过去完成式表示过去的动作.
例如：
I’d rather you hadn’t done that．我真希望(宁愿)你没做过那件事.
二、在主语从句中
1．在句型“h is／was+过去分词+that从句”中,当过去分词为“suggested,ordered,desired,insisted, required,demanded,requested,decided,proposed,urged’’等时,从句中要用“should+动词原形”(should可省略).例如：
h is desired that everyone(should)get erything ready bY toniShL要求每一个人在今晚之前要将一切准备好.
It is requested that Miss Zhang(should) give a performance at the party．请求张小姐在晚会上表演一个节目.
2．在句型“h is／Was+形容词+that从句”中,当形容词为“important,necessary,strange,natural’’等时,从句中要用“should+动词原形”(should可省略).例如：
It is important and necessary that we should master a foreign language．掌握一门外语对我们来说是重要的和必要的.
It is strange that he (should) refuse your help．他竟然拒绝你们的帮助,真奇怪.
3．在句型“h is／was+名词+that从句” 中,当名词为“a pity,a shame,no wonder’等时,从句中要用“should+动词原形”(should可省略).例如：
It is a great pity that he should be sO selfish.真遗憾,他竟然那么自私.
三、在同位语从句或表语从句中
在名词“suggestion,proposal,idea,plan,order,advice’’等后面的同位语从句或表语从句中,用“should+动词原形”(should可省略).例如：
I made a proposal that we(should)hold a meeting next week．我提出了我们下个星期开会的建议.(同位语从句)
His suggestion that the meeting(shoald)be held in this room has been accepted．他的关于在这个房间召开会议的建议被采纳了.(同位语从句)
My idea is that we(should)get more people to attend the conference．我的想法是我们多找些人来参加会议.(表语从句)
四、在定语从句中
在句型“h is(high)time+(that)从句”中,谓语须用虚拟语气.用过去式表示现在或将来的意念,意为“现在是该做某事的时候了”.
例如：
h iS(hieh)time(that)we went home．我们该回家了.
五、在状语从句中
1．在假设条件句的if条件从句中
假设条件句一般是由“if引导的条件从句+主句”构成.if从句中的谓语动词要用虚拟语气的形式.if从句的假设可以是与现在事实相反的条件、与过去事实相反的条件或者与将来不太可能成为事实的条件.下面分述表示这三种条件的if从句的结构：
①与现在的事实相反,其句子结构为“If+主语+were／谓语动词的过去式”.例如：
If 1 were you,I shouldn’t do that．如果我是你,就不会做那件事了.
We would gO with you if we had time．如果我们有时间的话,就和你一道去了.
We could ask him if he were here．如果他在这儿,我们就可以问他了.
②与过去的事实相反,其句子结构为“If十主语+谓语动词的过去完成式”.例如：
If he had seen you yesterday,he would have asked you about it如果昨天他见到你,他就会问你那件事了.
If you had come earlier,you would have met him．如果你早点儿来,就会遇到他了.
1 would have called you if I had known your telephone number．如果我知道你的电话号码,就打电话给你了.
③表示将来不太可能实现的条件,其句子结构为“If+主语+动词过去式／were to+动词原形／should+动词原形”.例如：
If he came tomorrow,he would find me in the schoo1．如果他明天来的话,会在学校找到我.
If it should rain,the crops would be saved．如果下雨,庄稼就有救了.
If it were to snow tomorrow,they would not go out．如果明天下雪,他们就不出去了.
注：在if从句中,如果含有“were,should,had’’时,可省去if而将“were,should,had’’置于句首,构成倒装句.例如：
Were l in your position,1 would go．如果我处在你的位子上,我就走了.
Had you arrived five minutes earlier,you could have seen them off．如果你早到五分钟,
你就可以给他们送行了.
Should he come,tell him to ring me up．如果他来的话,叫他打电话给我.
2．在目的状语从句中
①在由lest
和in case等引导的目的状语从句中,用“should+动词原形” (should可省略).例如：
He ran away lest he(should)be seen．他跑走了,以免被人看到.
She explained again and again in case he (should)misunderstand her．她解释了一遍又一遍,以免他误解她.
in case等引导的目的状语从句中的谓语有时也可用陈述语气.此时,从句表示的就是真实情况,而不是虚拟情况.例如：
Take warm clothes in case the weather iS cold．带上厚衣服,以防天气变冷.
②在由“so that…”和“in order that…”
引导的目的从句中,要用“can／could／may／might／would+动词原形”,以表示目的并非事实.例如：
She stayed at home for a few days sO that
she might／could take care of her sick mother． 她在家呆了几天,以便照顾她生病的母亲.
③在由“for fear that…”引导的从句中,用“should+动词原形”(有时也可用may／might／would).例如：
He worked hard for fear that he should fail．他努力学习,害怕考试不及格.
3．在方式状语从句中
由as if和as though等引导的方式状语从句中,如果从句所表达的情况是虚拟的,则①常用动词的过去式来表示与现在或当时的情况相
反；如果是BE动词,则用were；②常用过去完成式来表示与过去的情况相反.例如：
She loves the child as i厂he were her own．她爱这孩子就好像是她亲生的.
(实际上不是她亲生的孩子)
Holding his head high,he walked past the pole and the soldiers as if they didn’t exist．他昂着头从旗杆和卫兵身旁走过,就像他们不存在似的.(实际上他们是存在的)
He speaks English as well as ifhe hadstudied in England．他英语说得这么好,好像他去英国学过英语似的.(实际上他没有在英国学过英语)
4．在原因状语从句中
在“I’m sorry that．—／We were surprised that一．／They were disappointed that．．．”等引导的表示原因的状语从句中,用“should十动词原形”.例如：
I’m sorry that he should be in such poor health．他的身体这么差让我很难过.
We were surprised that she should be so stubbom．她这么固执让我们感到奇怪.
上述句子有时也可以用陈述语气,但这仅表示所叙述的是事实,而不表示讲话人的情绪.