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

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. injure　b. injured 　c. had injure　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。(答案是a)

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。

第二节：其他形式的条件句中的虚拟语气 一、用“without/but for/in the absence of ”表示“要不是”，“如果没有”(相当于if it were not for…)表示条件时，句中一般用虚拟语气。(也可用陈述语气) Without your help, I couldn' t finish my work on time. In the absence of water and air, nothing could live.

(三)、表示与将来事实相反的虚拟条件句(对将来的事实实现的可能性不大)。其句子结构为： 从句：If + 主语+ should (或were) + 动词原形+…… 主句：主语+ would (could, should, might) + 动词原形+…… 例如： ⑴、If I were to work at this problem, I would do it in another way.要是我来解这道难题，我会用另外一种方法的。 ⑵、If you were to do such a thing again, you would be punished. 如果你再做这样的事情，就会受到惩罚。 ⑶、If I should work harder, I could make much more progress.假如我更努力学习的话，我会取得更大的进步。(事实上我不可能努力学习) ⑷、If it should rain tomorrow, I would stay at home.如果明天下雨的话，我将待在家里。(根据天气情况，明天不可能下雨) ⑸、If he should come, I could ask him for some advice.万一他来了，我就能够向他请教。(事实上他来的可能性很小) ⑹、If he came tomorrow, I would do it with him.如果明天他来的话，我将和他一起做此事。(事实上他来的可能性很小) ⑺、 If it should rain, the crops would be saved.(从句动词用should rain，主句动词用be)如果天下雨，庄稼可能就收获了。 ⑻、 If he were to go fomorrow, he might tell you.(从句动词用were to, 主句动词用tell)如果明天他走的话，他可能会告诉你。 ⑼、 If he were here, I would give him the books.(从句动词用were, 主句动词用give)如果他在这儿，我可能会把书给他。 注意：如果动作在进行中，从句(不是主句喔)要用："If + 主语+ 过去进行式动词 +……" ⑽、 If she were staying here now, I would let her ride my horse.(从句动词用were staying, 主句动词用let)如果她现在留在这儿，我可能会让她骑我的马。

(二)、表示与过去事实相反的虚拟条件句。其句子结构为： 从句：If + 主语+ had +过去完成式动词+ …… 主句：主语+ would (should, could, might) + have +过去完成式动词+…… 例如: ⑴、If you had taken my advice, you would not have made such a mistake.如果你听了我的劝告,就不会犯这样的错误。(事实上你没有听我的劝告) ⑵、I shouldn’t have been able to write such good novels if I hadn’t lived among the peasants for five years.如果我不是和农民生活了五年，就不可能写出这样好的小说。(事实上我和农民生活了五年) ⑶、If you hadn’t invited me, I shouldn’t have come to the party.如果你不邀请我，我就不会来参加你的舞会。(事实上你邀请了我) ⑷、If it hadn’t been for your help, I shouldn’t have finished this work on time. 要是没有你们的帮忙，我就不会按时完成了这项工作。(事实上你们帮助了我) ⑸、If he hadn’t broken the law, he wouldn’t have been put in prison.如果他不违法的话，就不会被打入监狱。(事实上他违法了) ⑹、If I hadn’t been ill yesterday, I might have come to school.昨天要是不生病，我是可能来上学的。(事实上我生病了) ⑺、If I had been your headmaster, I should have dismissed you from school. 我要是你们校长的话，就把你开除学籍了。(事实上我不是) ⑻、 If you had studied harder last term, you could have passed exam.(从句动词用had studied, 主句动词用have passed)如果你在上个学期用功一些，你就会在考试中过关了。 ⑼、 If you had taken my advice, you wouldn't have failed in the exam.(从句动词用had taken, 主句动词用have failed)如果你当时听从我的劝告的话，你就不会在考试中失败了。 ⑽、 If you had got up earlier, you could have caught the train.(从句动词用had got up, 主句动词用have caught)如果你起身得早一点，你就会赶得上火车了。 ⑾、 If it had snowed, I would have skied in the park.(从句动词用had snowed, 主句动词用have skied)如果下雪的话，我就可在公园里滑雪了。 注意：如果动作在进行中，主句要用："主语+ would + have + 完成进行式动词 +…… ⑿、 If they had been here, he would have been speaking to them.(从句动词用had been, 主句动词用have been speaking)

在It is +名词+that的主语从句中，常用虚拟语气，表示建议、命令、请求、道歉、怀疑、惊奇等。这类名词

有：advice ，decision ，desire ，demand ，idea，motion ，order，pity ，preference ，proposal，recommendation ，

requirement，resolution，shame，suggestion，surprise，wish，wonder等。

⑴、It is my proposal that he be sent to study further abroad．我建议派他去国外进一步学习。

第三节：虚拟语气用在表语从句或同位语从句中

当某些表示建议、请求、命令等主观意向的名词作主语时，其后的表语从句或同位语从句需用虚拟语气，其表达形式为should +动词原形或直接用动词原形。这类名词常见的有：

demand (要求), desire (请求),requirment (要求)

advice (劝告), recommendation (建议),suggestion (建议)

order (命令)

necessity (必要地), preference (优先)

proposal (计划), plan (计划), idea (办法)，

recommendation以及plan，idea，resolution等。

We are all for your proposal that the discussion be put off．我们都赞成你提出的将讨论延期的建议。

The suggestion that the mayor present the prizes was accepted by

everyone．由市长颁发奖金的建议被每个人接受。

⑴、 The advice is that we (should 可省略，下同) leave at once.

(名词advice，should + leave) (表示加以劝告)

⑵、 My idea is that we (should) get more people to attend the

conference.

(idea, should + get) (表示做出主意)

⑶、 I make a proposal that we (should) hold a meeting next week.

(proposal, should + hold) (表示做出计划)

⑷、 The judge assented to the suggestion that .

［A］both of the criminals will soon be set freedom

［B］some of the criminals there are of guilt only

［C］the girl was to be paroled in the custody of a welfare society

［D］the prisoner be sentenced to death

10.I don't think it advisable that Tom be assigned to the job since he has no experience．汤姆缺乏经验，指派他做这项工作我认为是不恰当的。