虚拟语气讲座

(3).Alan talked about Rome as if he were a Roman．艾伦谈起罗马来好像他是个罗马人一样。
(4).John pretends as if he didn' t know the thing at all, but in fact he knows it very well.(用过去式表示与现在事实相反的假设)
(5). He pretends as if he didn't know the thing at all, but in fact he knows it very well.（用过去式表示与现在事实相反的假设）他假装好象完全不懂那事，其实他对那事非常了解。
2. 表示过去想象中的动作或情况，谓语动词用过去完成式。如：
(1).The tree looked as if it ______ for a long time.
A. hasn't watered B. didn't water
C. hadn't bee watered D. wasn't watered
那棵树看上去好象很久没人给浇水了。（答案是c）
(2).The old man looked at the picture, he felt as though he had gone back to time 20 years ago.（用过去完成式表示与过去相反的事实）
(3). The old man looked at the picture, he felt as though he had gone back to time 20 years ago.(用过去完成式表示与过去相反的事实)那老人看着照片，他觉得仿佛回到20年前的时光。
3.表示与将来事实相反:
(1).They talked and talked as if they would never meet again (would+动词原形，表示与将来事实相反)
(2). They talked and talked as if they would never meet again.(would + 原形动词meet，表示与将来事实相反)他们谈了又谈，仿佛他们不会再相见的样子。
注: 在as if / as though 句中, 如果有可能成为事实, 用陈述语气.
He looks as if he is going to be ill.
第二节：虚拟语气用在lest，for fear that及in case引导的目的状语从句中
在由lest等引导的目的状语从句中需用虚拟语气，表示"以防，以免"等意思，其谓语动词多由should ＋动词原形构成，should也可省略。
例如：
⑴、He was punished lest he should make the same mistake again．他被处以惩罚以免他再犯。
⑵、The mad man was put in the soft-padded cell lest he _____ himself.
a. injureb. injured c. had injured. 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。（答案是a）
第三节：介词短语表示虚拟
有时假设的情况并不以条件从句表示出来，而是通过一个介词短语来表示，或通过上下文或其他方式表示出来。如but for, but that…, in case of, otherwise, supposing, under more favourable condition, without 等表示让步假设。
1).He worked very hard; otherwise he might have failed. (他刻苦工作，不然他就失败了。)
2).We could have done better under more favorable conditions.(假设我们有更有利条件，我们还会做得更好。)
3). But for his help，I .
［A］should not have succeeded
［B］had not succeeded
［C］did not succeed
［D］have not succeeded
4). But that he came to help me, I .
［A］could not have succeeded
［B］did not succeed
［C］could not succeed
［D］can't but succeed
第四节：虚拟语气用在It is（about ／high）time ＋that定语从句中
在It is（about／high）time ＋that定语从句中需用虚拟语气，表示"该做……的时候了"，其动词形式用一般过去时或should ＋动词原形。
(1).It's already 5 o'clock now．Don't you think it's about time we went home？现在已经5点钟了，你不认为我们应该回家了吗？
(2).It is about time you were in bed.
(3).It is high time we left.
(4).It is the first time I came here.
注：
1、在this is the first time ／second time that．．．句型中，从句中谓语动词用陈述语气完成时态。
例如：
Is this the first time that you have visited Hongkong？这是你第一次参观香港吗？
2、It's time to do something有别于It's time that．．．
第五节：在if only 引起的感叹句中需用虚拟语气
谓语动词用过去式或过去完成式(谓语动词与wish宾语从句的虚拟形式相同).
⑴、If only he didn't drive so fast! (现在)
⑵、If only she had asked someone's advice.(过去)
⑶、If only the rain would stop.(将来)
例题解析:
⑷、Look at the terrible situation I am in! if only I ____ your advice.
A. follow B. had followed C. would follow D. have followed
if only 引出感叹句，意思是"要是……多好"，表示说话人的一种愿望，希望发生（事实上不可能发生）与过去事实相反的情况。本句的全句意思是："看我现在的处境多糟糕！要是我听从你的劝告多好"。事实上，句中的"我"没有听从劝告，所以处境很糟糕。
题中空格处应当用虚拟语气，答案是B。
第六部分：虚拟语气从句中should可以省略的情况
1. 在建议,要求,命令,想法后的动词后的从句（宾语从句）里, 用should + 动词原形, should 可以省略. 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.
如：
⑴、His doctor suggested that he (should) take short leave of absence.
⑵、The author proposed that TV (should) be turned off at least one hour every day.
2. 在建议,要求,命令,想法后的名词后的从句（表语从句，同位语从句）里, 用should + 动词原形, should可以省略. 如：
advice, agreement, command, decision, decree, demand,
determination, indication, insistence, order,
preference, proposal, request, requirement, stipulation etc.
例如：
⑴、It was Bill's suggestion that everyone (should) have a map.
⑵、His suggestion was that everyone (should) have a map.
⑶、He gave us a suggestion that everyone (should) have a map.