作业帮求高中英语虚拟语气讲解~
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求高中英语虚拟语气讲解~
★ 高考英语虚拟语气专题讲座★
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★ 语气是一种动词形式,用以表示说话者的意图或态度.英语中有三种语气：陈述语气,疑问语气,虚拟语气.
虚拟语气定义：虚拟语气表示所说的话只是一种主观愿望、假设或建议等.
虚拟语气的学习重点：
1. 虚拟语气的在条件句中的基本用法和四个基本情态动词的用法.
2. 虚拟语气的倒装.（if省略,条件句中中有had, should, were）.
3. 两种错综虚拟语气.
4. 含蓄条件句中的虚拟语气.
5. 过去的计划,打算,愿望等未曾实现时的虚拟语气.
6. 特殊句型中的虚拟语气：两个.重点为wish后宾语从句中的虚拟语气及as if和as though从句中虚拟语气的表示法.
7. 虚拟语气在名词性从句中的应用.即用来表示要求、建议、命令、提议、意愿等的名词性从句.
8. 不清惜条件的虚拟语气.
★★★虚拟语气在条件句中的用法列表如下：
相关时态 主句形式 从句形式 例句
与现在事实相反 Should\would\could\might+do（动词原形） 过去式（be动词各人称都用were） If I were you, I should \would make full use of my time to study.
与过去事实相反 Should\would\could\might+have done（动词过去分词） Had+done(过去分词) If you had come earlier, you would have met him.
与将来事实相反 Should\would\could\might+do（动词原形） 1. 过去式（be动词各人称都用were）
2. should+动词原形
3. were to +动词原形 If it should rain tomorrow, the crops would be saved.
★★★注意四个情态动词的用法：
1. 若表示在某一假设的条件下,必然而然就会发生某事,第一人称可用should或would, 而二、三人称只用would.
2. 若表示在某一假设条件下就能够干某事,各人称都用could.
3. 如果表示在某种假设条件下有可能会发生某事,各人称都用might.
★★★虚拟语气倒装
请看典型考题：__________ your address,I would have written to you.
A. Did I know B. Were I to know C. Had I known D. If I should know
此题应选 C.这是虚拟语气的倒装形式.当虚拟条件句中含有 were,had,should,could等动词时,可以将if省略,然后将 were,had,should,could 等词移至句首：
1. If he should fail,he would kill himself. →Should he fail,he would kill himself. 万一失败,他就会自杀.
2. If I were you,I would do it at once. →Were I you,I would do it at once. 假若我是你,我就会马上做.
3. If I could do it,I would. →Could I do it,I would. 要是我能做此事,我一定会做.
4. If he had seen you yesterday,he would haveasked you about it.
→Had he seen you yesterday,he would haveasked you about it. 他昨天要是看到了你,他就会问你这事了.
注意：顺便说一句,以上移至句首的 had不一定是助动词,如果是实义动词也可倒装：
5. If he had money,he would buy a car. Had he money,he would buy a car. 他要是有钱,他就会买一辆小车.
将下列倒装句恢复正常：
a. Were it not for the fact that you are ill, I would give you a good beating.
要不是因为你有病这一事实,我就会狠揍你一顿.
b. Had he asked me, I would have given him my advice.要是他请求我的话,我就会给他建议的.
c. Were it to snow tomorrow, the hunter would not go hunting.万一明天下雪,猎人就不去打猎了.
★★★错综虚拟语气
How I wish I had studied harder when I was in school!
If you had, you ____ work into late every day nowadays.
A. don’t B. wouldn’t C. didn’t D. won’t
[解析]“要是我在校时能够更加努力地学习,那该多好啊!”“要是你当时努力学习的话,你现在就不会每天都工作那么晚了.”根据句意,条件与过去事实相反,而主句与现在事实相反.
常见的两种错综虚拟语气：
1．从句与过去事实相反相成,而主句与现在事实相反.例如：
If you had not been strict with me when I was young, I could not be such a successful person now.如果我年轻时你没有对我严格要求的话,我现在就不可能是这么成功的一个人.（这种虚拟语气的特点是主句中常含有时间准状语now 或nowadays）
2. Should anyone come and ask for me, tell them I will come back tomorrow.万一有人来找我,告诉他们我明天回来.（主句为祈使句,条件句与将来事实相反,表示说话人认为某件事情发生的可能性很小.）
★★★含蓄虚拟条件句
含蓄虚拟条件句是指句中没有明显的虚拟条件句,而是利用其他手段来暗示存在虚拟条件.这类用法主要见于以下七种方式：
1. 将条件隐含在不定式短语中.
I should be happy to go with you. 如果能与你一起去,我将很高兴.(=I should be happy if I could go with you.)
To have studied harder, you would have passed the examination. 你学习更用功些,你早就考及格了.(=if you have studied harder, you…)
2. 将条件隐含在分词短语中.
Born in better times, he would have been a scholar. 如果出生在好时代,他早就成为学者了.(=If he had been born in better times, he …)
Failing this time, what would you do? 假若这次失败,那你怎么办?(=If you failed this time, what…)
Walking alone in the dark, Mary would be terrified. 要一个人单独在黑暗中走,玛丽会感十分害怕.(If Mary walked alone in the dark, she…)
3. 将条件隐含在介词短语中.
Without air, no one could live. 没有空气,人就不能活.(=If there were no air, no one could live.)
But for his help, he would have failed. 要不是有他的帮助,他就会失败了.(=If it hadn’t been for his help, he would have failed.)
常用的介词或介词短语,如but for, but that, without, in case of, under, under more favorable condition等.
4. 将条件隐含在名词短语中.
A true friend would not have betrayed me.
若是真正的朋友,就不会背弃我.(=If he had been a true friend, he would…)
A few hours earlier, and you would have seen the famous writer.
要是你早来几个小时,你就见到这位著名的作家了.(If you had come a few hours earlier, you…)
5. 将条件隐含在某些连词(如or, or else, otherwise等)中：
具体用法如下：它们后的句子如果说的不是客观事实,它们前边的句子采用陈述语气,后边的句子采用虚拟语气.
○1 句子（一般现在时）+ or, or else, otherwise + 句子（谓语部分：should\would\could\might等+ 动词原形）
○2 句子（一般过去时）+ or, or else, otherwise + 句子（谓语部分：should\would\could\might等+ have done）
I didn’t know that he was a cheat, or else I wouldn’t have believed him.
我不知道他是个骗子,不然我也不会相信他了.(or else=if I had known he was a cheat))
I’m really very busy, otherwise I would certainly go there with you.
我真的是太忙了,不然我就会同你一道去了.(otherwise=if I were not so busy))
6. 将条件隐含在定语从句中.
Anyone who had seen that painting might have taken it for a photo.
凡是看过那画的人,都可能把它看成是照片.(=If anyone had seen that painting…)
7. 将条件隐含在一定的上下文中.
Don’t bother to read all these papers. It would take too long.
不要费事看所有这些文件了,那会花太多时间.(=…If you read all these papers, it would take too long)
常用来表示含蓄虚拟条件的手段连词如：so that, unless, in case, supposing, lest, provided(倘若……),for fear that(惟恐) , on condition that, if only(要是……就好了)等.
(注：lest, for fear that和in case引起的从句中谓语动词多用should+动词原形,但可以不用虚拟语气,而用动词的陈述语气形式.)例如：
★ The foreign teacher spoke slowly in case we misunderstood him.这位外籍教师说得很慢以免我们听不懂.
Care must be taken in using this method lest overflow should occur.
在使用此法时要小心谨慎,以免会发生溢流现象.
★★★过去的计划打算愿望等未曾实现时的虚拟语气
1. 表过去愿望未曾实现时,常用would like to have done sth. 或would have liked to do sth.(前者常用)
I would like to have gone to the celebration, but I couldn’t get away. 我本来想参加庆祝会,但未能脱开身.
2. 表示过去本来该干某事但没有干时,用should\ought to have done sth. 若表示本来不该干但却干了某事时,用should not\ought not to have done sth.
The criminal should have told the truth, but he refused to. 那罪犯本来应该说出实情,但他不肯说.
3. 表示过去本来有能力干某事,但未能干成时用could have done sth.
I could have lent you the money, but you did not turn to me for help. 我本来能借给你那笔钱,但你没有向我求助.
4. 表示过去本来有可能干某事,但未能干成时用might have done sth.
You might have been chosen, but you gave up the chance. 你本来有可能被选上的,但你放弃了那个机会.
5. 表示过去本来愿意干某事,但未能干成时用would have done sth.
The cook would have helped you, but his wife stopped him. 那厨师本来愿意帮助你,但他妻子制止了他.
6. hope, want, expect, plan等动词表示过去愿望、计划、打算等未曾实现时,把谓语动词用成过去完成时或把它们后面的不定式用成完成式.
I had hoped to become a poet, but I turned teacher instead. 我本希望当个诗人,但我却当了老师.
I hoped to have become a poet, but I turned teacher instead.
My playmate hoped to have entered a key university last year, but his wish didn’t come true.
我的伙伴本打算进入一个重点大学,但他的梦想没能实现.
7. be to do sth.句型表示过去计划安排未曾实现时,用was\ were to have done sth结构.
The European tourists were to have arrived by ten, but they were caught in a shower and delayed.
那些欧洲的游客本来10点到达,但他们遇上了阵雨,被推迟了.
The building was to have been completed by the end of last month, but the plan failed.
这栋楼本来计划上个月底建完,但计划失败了.
8. be going to句型表过去个人打算未曾实现时,用was\were going to结构.
--Did you go to the museum yesterday?
--No, I was going to, but something urgent happened at the last moment.
你昨天到博物馆去了吗? 我本来打算去,但在最后的片刻发生了紧急的事情.
I was going to meet you at the station, but I had to work extra hours writing a report for my boss.
我本来打算去车站见你,但我不得不在工作几个小时给我老板写份报告.
★★★虚拟语气在名词性从句中的使用：
（一） 主语从句中的虚拟语气
在It is ＋形容词／某些动词的过去分词＋主语从句的结构中,从句的谓语动词须用动词原形或 should ＋do的形式.这些类型包括：
1、It’s important…类 形容词
这一类型主要包括It is (was) important (necessary, desirable, imperative, advisable)that. . .句型.如：
It is impossible that he should go home. 他不可能会回家去.
It is necessary that I should return it right now. 我有必要马上把它还回去.
It is important that we should speah politely. 我们说话要有礼貌,这是很重要的.
It is not necessary that everyone be a scientist. 没有必要使每一个人都成为科学家.
It is imperative that we should practise critidsm and self-criticism. 应当进行批评与自我批评.
2、It’s a pity…类 名词
It is a pity that she should fare so badly. 她竟吃得这么差,真可怜.
It’s a pity that he should be so obstinate. 真遗憾他竟这样倔犟.
It was a pity that you couldn’t come. 你不能来,真是太遗憾了.
It is a pity that she failed the driving examination. 她没通过驾驶考试真是遗憾.
It is his desire that a medical man should stay here. 他希望有一个医务人员留在这里.
3、It’s desired…类 某些动词的过去分词
这种主语从句还常用在It is (was) desired (suggested, settled, proposed, requested, decided, etc. ) that...句型.如：
It is requested that a vote be taken. 建议付诸表决.
It is settled that you leave us, then? 那么你肯定要离开我们罗?
It was proposed that this matter be considered at the next meeting. 有人提议这事下次会议再讨论.
★ It is desired that this rule should be brought to the attention of the staff. 希望这条规则引起全体职员的注意.
【特别说明】
(1) 在现代英语中,有时也可不用虚拟语气而用陈述语气,但初学者宜慎用.
(2) 在It is amazing (strange, surprising, astonishing, a pity, a shame)以及 I am surprised (sorry) 和I regret等结构后的that 从句中有时也用should,表示说话人的惊异、懊悔、失望等情感,常含有“竟然”之意：
It’s strange that he should be so rude. 他竟如此无礼,真是奇怪.
I’m surprised that he should have failed. 他竟然失败了,这使我很吃惊.
若不用虚拟语气也可以,则不带感情 色彩,比较：
It’s a pity that he failed the exam. 他考试没及格,真是遗憾.
It’s a pity that he should have failed the exam. 他考试竟没及格,真是遗憾.
decided（决定的）、 important（重要的）、 ordered（命令的）、 advisable（合理的）、
demanded（要求的） desire（期望的）、 desirable（合乎需要的）、 essential（紧要的）、
insistent（坚持的）、 natural（自然的）、 preferabl（更可取的）、 proposed（建议的）、
recommended（推荐的）、required（要求的）、 urgent（紧迫的）、 vital（极其重要的）
appropriate（适当的）、 arranged（安排好的）、 better（较好的）、 imperative（迫切的）、
possible（可能的）、 probable（可能的）、 resolved（决心的）、 strange（奇怪的）、
suggested（建议的）
It is highly desirable that a new mayor be appointed for this city．这座城市急需任命一位新市长.
（二）宾语从句用虚拟语气的10种类型
1、I wish后的宾语从句 （ 略）
We wish he didn’t smoke. 我们希望他不吸烟.
I wish prices would come down. 我希望物价能降下来.
I wish the train would come. 我希望火车会来.
2、表示“坚持”后的宾语从句
主要是指insist的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美国英语中通常可以省略.如：
I insisted that he (should) stay. 我坚持要他留下.
He insisted that I (should) go with them. 他坚持要我同他们一起去.
Rose insisted that he be present. 罗斯坚持要他出席.
The detective insisted that he should have a look. 警探坚持要查看.
注意：动词insist后接宾语从句时,除可用虚拟语气外,也可用陈述语气,两者的区别是：若谓语动词所表示的动作尚未发生,或尚未成为事实,则用虚拟语气；若谓语动词所表示的动作已经发生,或已经成为事实,则要用陈述语气.比较：
He insisted that I had read his letter. 他坚持说我看过他的信.
He insisted that I should read his letter. 他坚持要我看他的信.
3、表示“命令”后的宾语从句
主要是指order, command的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美国英语中通常可以省略.如：
He ordered that it (should) be sent back. 他命令把它送回去.
Thejudge ordered that the prisoner should be remanded. 法官命令被告还押.
The King ordered that the man be released. 国王命令释放那人.
He commanded that we (should) attack at once. 他命令我们立即发起进攻.
4、表示“建议”后的宾语从句
主要是指advise, suggest, propose, recommend等的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美国英语中通常可以省略.如：
He suggested that we should leave early. 他建议我们早点动身.
The doctor advised that he change his job. 医生劝他换工作.
They recommend that this tax be abolished. 他们建议取消这种税.
I suggest that we (should) have lunch right now. 我建议我们现在就吃午饭.
The committee proposed (that) Mr. Day be elected. 委员会建议推选戴先生.
The doctor advised [suggested] that he (should) not smoke. 医生建议他不要抽烟.
I propose that the matter be put to the vote at once. 我提议对此问题立刻进行表决.
He proposed that Mr. O’Leary be the chairman. 他提议奥列利先生担任主席.
She suggested that I (should) be responsible for the arrangements. 她建议我来负责进行安排.
注意：与动词insist相似,动词suggest后接宾语从句时,除可用虚拟语气外,也可用陈述语气,两者的区别也是：若谓语动词所表示的情况尚未成为事实,则用虚拟语气,此时suggest通常译为“建议”；若谓语动词所表示的情况为既成事实,则要用陈述语气,此时的suggest通常译为“表明”、“认为”.比较并体会：
He suggested that we (should) stay for dinner. 他建议我们留下吃饭.
What he said suggested that he was a cheat. 他说的话表明他是个骗子.
I suggested that you had a secret understanding with him. 我觉得你与他心照不宣.
5、表示“要求”后的宾语从句
9、表示“希望”“打算”后的宾语从句
主要是指动词desire, intend后的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美语中通常省略.
She desires that he do it. 她希望他做此事.
They intended that the news (should) be suppressed. 他们打算封锁这条消息.
I desire the patient should have a bath every day. 我希望病人每天洗澡.
10、表示“指示”后的宾语从句
主要是指动词direct后的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美国英语中通常可以省略.
The general directed that the prisoners should be set free. 将军指示释放那些俘虏.
（三）表语从句和同位语从句
有些名词引起的表语从句或同位语从句中,谓语动词须用动词原形或should ＋do的形式.
这些名词包括：
advice（忠告）、 decision（决定）、 demand（要求）、 desire（渴望）、 idea（想法）、
motion（提议）、 necessity（必要性）、 order（命令）、 plan（计划）、 preference（偏爱）、
proposal（建议）、 recommendation（推荐）、requirement（要求）、suggestion（建议）等.
例句13：His proposal is that we turn off TVfor half an hour every day．他建议我们每天少看半个小时的电视.
特别提示：从以上的各类从句中我们可以得到以下的推论,即当一个动词后面的宾语从句中要使用（should）＋do的虚拟语气形式时,则可推理出用法相同的一组从句.以动词advise为例：
（1）I advise that we stay and wait here．（动词后的宾语从句）
（2）It is advised that we stay here．（It is ＋动词的过去分词＋that引导的主语从句）
（3）It is advisable that we stay here．（It is ＋由该动词转换的形容词＋that引导的主语从句）
（4）My advice is that we stay here．（由该动词转换的名词后的表语从句）
（5）I offered the advice that we stay here．（由该动词转换的名词后的同位语从句）
（6）I think it advisable that we stay here．（由该动词转换的形容词作宾语补足语,it为形式宾语,真正的宾语从句中使用虚拟语气）
以上六类从句中所使用的都为（should）＋do的虚拟语气形式.
★★★wish后宾语从句用虚拟语气
一． Wish本身为现在时,后面得宾语从句如果与现在存在状态相反的愿望,从句中谓语动词采用过去时或过去进行时,遇到be动词时各人称都用were.
二． Wish本身为过去时,后面得宾语从句如果与过去存在状态相反,从句中谓语动词采用过去时,遇到be动词时各人称都用were.
三． 凡发生在谓语（wish）以前的动作,从句中的虚拟语气谓语的结构形式是过去完成时, 即had+动词过去分词或would \ could + have done.
四． 凡发生在谓语（wish）以后的动作,从句中的虚拟语气谓语的结构形式是过去将来时,即（would +动词原形）,如果用到情态动词can,各人称都用could.
五． I wish + 从句的结构还可以转换成if only+ 从句结构.If only后也要采用虚拟语气,其构成及意思与I wish + 从句完全一样.
六．从句的时态只与从句所指的时间有关,而与wish的时态无关,比较：
I wish I were not so busy. 但愿我不那样忙碌. （与现在相反）1
I wish I were [was] better looking. 要是我长得漂亮些就好了. （与现在相反）1
I wished I were rich. 当时我后悔自己没有钱. （与过去相反）2
I wished I had been rich. 当时我后悔自己曾经没有钱. （与过去相反）3
She wished she had stayed at home. 她后悔的是她当时要是留在家里就好了. （与过去相反）3
I wish you would go with us tomorrow. 要是你明天同我们一起去就好了. （与将来相反）4
I wish you wouldn’t look down on this kind of work. 我希望你不要看不起这种工作. （与将来相反）4
I wish you wouldn’t smoke any more. 我希望你不再抽烟了. （与将来相反）4
I wish you would be more respectful to your father. 我希望你对你父亲更尊敬些. （与将来相反）4
I wish I could be of some use. 我希望我能有什么用处. （与将来相反）4
If only I were you.= I wish I were you. 我要是你就好了. （与现在相反）5
★★★虚拟语气的几个特殊句型：
★★★would rather后句子用虚拟语气：would rather后接句子时,句子谓语习惯上要用虚拟语气,具体用法为：
1．一般过去时表示现在或将来的愿望
I’d rather you went tomorrow (now). 我宁愿你明天(现在)去.
I’d rather you came next Saturday. 我宁愿你下星期六来.
I’d rather you were happy. 我愿你快乐.
I’d rather she sat next to me. 我宁愿她挨着我坐.
I’d rather Jack left on an earlier train. 我宁愿杰克乘前一班火车走.
You always go without me and l’d rather you didn’t. 你总是不带我去,我可不愿意你这样.
“Shall I open the window? ” “I’d rather you didn’t. ”“我要不要把窗子打开? ” “我看不要打开好.”
2. 用过去完成时表过去的愿望
I’d rather you hadn’t said it. 我真希望你没有这样说过.
I’d rather you hadn’t done that. 我宁愿你没这样做.
l’d rather you had been / hadn’t been present.我 (宁) 愿你当时在场 / 不在场.
l’d rather he had told / hadn’t told me about it 我 (宁) 愿他告诉了 / 未告诉我这件事.
Katie went by car and I’d rather she hadn’t. 凯蒂是坐汽车去的,我宁愿地不坐汽车去.
★
★
★ 语气是一种动词形式,用以表示说话者的意图或态度.英语中有三种语气：陈述语气,疑问语气,虚拟语气.
虚拟语气定义：虚拟语气表示所说的话只是一种主观愿望、假设或建议等.
虚拟语气的学习重点：
1. 虚拟语气的在条件句中的基本用法和四个基本情态动词的用法.
2. 虚拟语气的倒装.（if省略,条件句中中有had, should, were）.
3. 两种错综虚拟语气.
4. 含蓄条件句中的虚拟语气.
5. 过去的计划,打算,愿望等未曾实现时的虚拟语气.
6. 特殊句型中的虚拟语气：两个.重点为wish后宾语从句中的虚拟语气及as if和as though从句中虚拟语气的表示法.
7. 虚拟语气在名词性从句中的应用.即用来表示要求、建议、命令、提议、意愿等的名词性从句.
8. 不清惜条件的虚拟语气.
★★★虚拟语气在条件句中的用法列表如下：
相关时态 主句形式 从句形式 例句
与现在事实相反 Should\would\could\might+do（动词原形） 过去式（be动词各人称都用were） If I were you, I should \would make full use of my time to study.
与过去事实相反 Should\would\could\might+have done（动词过去分词） Had+done(过去分词) If you had come earlier, you would have met him.
与将来事实相反 Should\would\could\might+do（动词原形） 1. 过去式（be动词各人称都用were）
2. should+动词原形
3. were to +动词原形 If it should rain tomorrow, the crops would be saved.
★★★注意四个情态动词的用法：
1. 若表示在某一假设的条件下,必然而然就会发生某事,第一人称可用should或would, 而二、三人称只用would.
2. 若表示在某一假设条件下就能够干某事,各人称都用could.
3. 如果表示在某种假设条件下有可能会发生某事,各人称都用might.
★★★虚拟语气倒装
请看典型考题：__________ your address,I would have written to you.
A. Did I know B. Were I to know C. Had I known D. If I should know
此题应选 C.这是虚拟语气的倒装形式.当虚拟条件句中含有 were,had,should,could等动词时,可以将if省略,然后将 were,had,should,could 等词移至句首：
1. If he should fail,he would kill himself. →Should he fail,he would kill himself. 万一失败,他就会自杀.
2. If I were you,I would do it at once. →Were I you,I would do it at once. 假若我是你,我就会马上做.
3. If I could do it,I would. →Could I do it,I would. 要是我能做此事,我一定会做.
4. If he had seen you yesterday,he would haveasked you about it.
→Had he seen you yesterday,he would haveasked you about it. 他昨天要是看到了你,他就会问你这事了.
注意：顺便说一句,以上移至句首的 had不一定是助动词,如果是实义动词也可倒装：
5. If he had money,he would buy a car. Had he money,he would buy a car. 他要是有钱,他就会买一辆小车.
将下列倒装句恢复正常：
a. Were it not for the fact that you are ill, I would give you a good beating.
要不是因为你有病这一事实,我就会狠揍你一顿.
b. Had he asked me, I would have given him my advice.要是他请求我的话,我就会给他建议的.
c. Were it to snow tomorrow, the hunter would not go hunting.万一明天下雪,猎人就不去打猎了.
★★★错综虚拟语气
How I wish I had studied harder when I was in school!
If you had, you ____ work into late every day nowadays.
A. don’t B. wouldn’t C. didn’t D. won’t
[解析]“要是我在校时能够更加努力地学习,那该多好啊!”“要是你当时努力学习的话,你现在就不会每天都工作那么晚了.”根据句意,条件与过去事实相反,而主句与现在事实相反.
常见的两种错综虚拟语气：
1．从句与过去事实相反相成,而主句与现在事实相反.例如：
If you had not been strict with me when I was young, I could not be such a successful person now.如果我年轻时你没有对我严格要求的话,我现在就不可能是这么成功的一个人.（这种虚拟语气的特点是主句中常含有时间准状语now 或nowadays）
2. Should anyone come and ask for me, tell them I will come back tomorrow.万一有人来找我,告诉他们我明天回来.（主句为祈使句,条件句与将来事实相反,表示说话人认为某件事情发生的可能性很小.）
★★★含蓄虚拟条件句
含蓄虚拟条件句是指句中没有明显的虚拟条件句,而是利用其他手段来暗示存在虚拟条件.这类用法主要见于以下七种方式：
1. 将条件隐含在不定式短语中.
I should be happy to go with you. 如果能与你一起去,我将很高兴.(=I should be happy if I could go with you.)
To have studied harder, you would have passed the examination. 你学习更用功些,你早就考及格了.(=if you have studied harder, you…)
2. 将条件隐含在分词短语中.
Born in better times, he would have been a scholar. 如果出生在好时代,他早就成为学者了.(=If he had been born in better times, he …)
Failing this time, what would you do? 假若这次失败,那你怎么办?(=If you failed this time, what…)
Walking alone in the dark, Mary would be terrified. 要一个人单独在黑暗中走,玛丽会感十分害怕.(If Mary walked alone in the dark, she…)
3. 将条件隐含在介词短语中.
Without air, no one could live. 没有空气,人就不能活.(=If there were no air, no one could live.)
But for his help, he would have failed. 要不是有他的帮助,他就会失败了.(=If it hadn’t been for his help, he would have failed.)
常用的介词或介词短语,如but for, but that, without, in case of, under, under more favorable condition等.
4. 将条件隐含在名词短语中.
A true friend would not have betrayed me.
若是真正的朋友,就不会背弃我.(=If he had been a true friend, he would…)
A few hours earlier, and you would have seen the famous writer.
要是你早来几个小时,你就见到这位著名的作家了.(If you had come a few hours earlier, you…)
5. 将条件隐含在某些连词(如or, or else, otherwise等)中：
具体用法如下：它们后的句子如果说的不是客观事实,它们前边的句子采用陈述语气,后边的句子采用虚拟语气.
○1 句子（一般现在时）+ or, or else, otherwise + 句子（谓语部分：should\would\could\might等+ 动词原形）
○2 句子（一般过去时）+ or, or else, otherwise + 句子（谓语部分：should\would\could\might等+ have done）
I didn’t know that he was a cheat, or else I wouldn’t have believed him.
我不知道他是个骗子,不然我也不会相信他了.(or else=if I had known he was a cheat))
I’m really very busy, otherwise I would certainly go there with you.
我真的是太忙了,不然我就会同你一道去了.(otherwise=if I were not so busy))
6. 将条件隐含在定语从句中.
Anyone who had seen that painting might have taken it for a photo.
凡是看过那画的人,都可能把它看成是照片.(=If anyone had seen that painting…)
7. 将条件隐含在一定的上下文中.
Don’t bother to read all these papers. It would take too long.
不要费事看所有这些文件了,那会花太多时间.(=…If you read all these papers, it would take too long)
常用来表示含蓄虚拟条件的手段连词如：so that, unless, in case, supposing, lest, provided(倘若……),for fear that(惟恐) , on condition that, if only(要是……就好了)等.
(注：lest, for fear that和in case引起的从句中谓语动词多用should+动词原形,但可以不用虚拟语气,而用动词的陈述语气形式.)例如：
★ The foreign teacher spoke slowly in case we misunderstood him.这位外籍教师说得很慢以免我们听不懂.
Care must be taken in using this method lest overflow should occur.
在使用此法时要小心谨慎,以免会发生溢流现象.
★★★过去的计划打算愿望等未曾实现时的虚拟语气
1. 表过去愿望未曾实现时,常用would like to have done sth. 或would have liked to do sth.(前者常用)
I would like to have gone to the celebration, but I couldn’t get away. 我本来想参加庆祝会,但未能脱开身.
2. 表示过去本来该干某事但没有干时,用should\ought to have done sth. 若表示本来不该干但却干了某事时,用should not\ought not to have done sth.
The criminal should have told the truth, but he refused to. 那罪犯本来应该说出实情,但他不肯说.
3. 表示过去本来有能力干某事,但未能干成时用could have done sth.
I could have lent you the money, but you did not turn to me for help. 我本来能借给你那笔钱,但你没有向我求助.
4. 表示过去本来有可能干某事,但未能干成时用might have done sth.
You might have been chosen, but you gave up the chance. 你本来有可能被选上的,但你放弃了那个机会.
5. 表示过去本来愿意干某事,但未能干成时用would have done sth.
The cook would have helped you, but his wife stopped him. 那厨师本来愿意帮助你,但他妻子制止了他.
6. hope, want, expect, plan等动词表示过去愿望、计划、打算等未曾实现时,把谓语动词用成过去完成时或把它们后面的不定式用成完成式.
I had hoped to become a poet, but I turned teacher instead. 我本希望当个诗人,但我却当了老师.
I hoped to have become a poet, but I turned teacher instead.
My playmate hoped to have entered a key university last year, but his wish didn’t come true.
我的伙伴本打算进入一个重点大学,但他的梦想没能实现.
7. be to do sth.句型表示过去计划安排未曾实现时,用was\ were to have done sth结构.
The European tourists were to have arrived by ten, but they were caught in a shower and delayed.
那些欧洲的游客本来10点到达,但他们遇上了阵雨,被推迟了.
The building was to have been completed by the end of last month, but the plan failed.
这栋楼本来计划上个月底建完,但计划失败了.
8. be going to句型表过去个人打算未曾实现时,用was\were going to结构.
--Did you go to the museum yesterday?
--No, I was going to, but something urgent happened at the last moment.
你昨天到博物馆去了吗? 我本来打算去,但在最后的片刻发生了紧急的事情.
I was going to meet you at the station, but I had to work extra hours writing a report for my boss.
我本来打算去车站见你,但我不得不在工作几个小时给我老板写份报告.
★★★虚拟语气在名词性从句中的使用：
（一） 主语从句中的虚拟语气
在It is ＋形容词／某些动词的过去分词＋主语从句的结构中,从句的谓语动词须用动词原形或 should ＋do的形式.这些类型包括：
1、It’s important…类 形容词
这一类型主要包括It is (was) important (necessary, desirable, imperative, advisable)that. . .句型.如：
It is impossible that he should go home. 他不可能会回家去.
It is necessary that I should return it right now. 我有必要马上把它还回去.
It is important that we should speah politely. 我们说话要有礼貌,这是很重要的.
It is not necessary that everyone be a scientist. 没有必要使每一个人都成为科学家.
It is imperative that we should practise critidsm and self-criticism. 应当进行批评与自我批评.
2、It’s a pity…类 名词
It is a pity that she should fare so badly. 她竟吃得这么差,真可怜.
It’s a pity that he should be so obstinate. 真遗憾他竟这样倔犟.
It was a pity that you couldn’t come. 你不能来,真是太遗憾了.
It is a pity that she failed the driving examination. 她没通过驾驶考试真是遗憾.
It is his desire that a medical man should stay here. 他希望有一个医务人员留在这里.
3、It’s desired…类 某些动词的过去分词
这种主语从句还常用在It is (was) desired (suggested, settled, proposed, requested, decided, etc. ) that...句型.如：
It is requested that a vote be taken. 建议付诸表决.
It is settled that you leave us, then? 那么你肯定要离开我们罗?
It was proposed that this matter be considered at the next meeting. 有人提议这事下次会议再讨论.
★ It is desired that this rule should be brought to the attention of the staff. 希望这条规则引起全体职员的注意.
【特别说明】
(1) 在现代英语中,有时也可不用虚拟语气而用陈述语气,但初学者宜慎用.
(2) 在It is amazing (strange, surprising, astonishing, a pity, a shame)以及 I am surprised (sorry) 和I regret等结构后的that 从句中有时也用should,表示说话人的惊异、懊悔、失望等情感,常含有“竟然”之意：
It’s strange that he should be so rude. 他竟如此无礼,真是奇怪.
I’m surprised that he should have failed. 他竟然失败了,这使我很吃惊.
若不用虚拟语气也可以,则不带感情 色彩,比较：
It’s a pity that he failed the exam. 他考试没及格,真是遗憾.
It’s a pity that he should have failed the exam. 他考试竟没及格,真是遗憾.
decided（决定的）、 important（重要的）、 ordered（命令的）、 advisable（合理的）、
demanded（要求的） desire（期望的）、 desirable（合乎需要的）、 essential（紧要的）、
insistent（坚持的）、 natural（自然的）、 preferabl（更可取的）、 proposed（建议的）、
recommended（推荐的）、required（要求的）、 urgent（紧迫的）、 vital（极其重要的）
appropriate（适当的）、 arranged（安排好的）、 better（较好的）、 imperative（迫切的）、
possible（可能的）、 probable（可能的）、 resolved（决心的）、 strange（奇怪的）、
suggested（建议的）
It is highly desirable that a new mayor be appointed for this city．这座城市急需任命一位新市长.
（二）宾语从句用虚拟语气的10种类型
1、I wish后的宾语从句 （ 略）
We wish he didn’t smoke. 我们希望他不吸烟.
I wish prices would come down. 我希望物价能降下来.
I wish the train would come. 我希望火车会来.
2、表示“坚持”后的宾语从句
主要是指insist的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美国英语中通常可以省略.如：
I insisted that he (should) stay. 我坚持要他留下.
He insisted that I (should) go with them. 他坚持要我同他们一起去.
Rose insisted that he be present. 罗斯坚持要他出席.
The detective insisted that he should have a look. 警探坚持要查看.
注意：动词insist后接宾语从句时,除可用虚拟语气外,也可用陈述语气,两者的区别是：若谓语动词所表示的动作尚未发生,或尚未成为事实,则用虚拟语气；若谓语动词所表示的动作已经发生,或已经成为事实,则要用陈述语气.比较：
He insisted that I had read his letter. 他坚持说我看过他的信.
He insisted that I should read his letter. 他坚持要我看他的信.
3、表示“命令”后的宾语从句
主要是指order, command的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美国英语中通常可以省略.如：
He ordered that it (should) be sent back. 他命令把它送回去.
Thejudge ordered that the prisoner should be remanded. 法官命令被告还押.
The King ordered that the man be released. 国王命令释放那人.
He commanded that we (should) attack at once. 他命令我们立即发起进攻.
4、表示“建议”后的宾语从句
主要是指advise, suggest, propose, recommend等的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美国英语中通常可以省略.如：
He suggested that we should leave early. 他建议我们早点动身.
The doctor advised that he change his job. 医生劝他换工作.
They recommend that this tax be abolished. 他们建议取消这种税.
I suggest that we (should) have lunch right now. 我建议我们现在就吃午饭.
The committee proposed (that) Mr. Day be elected. 委员会建议推选戴先生.
The doctor advised [suggested] that he (should) not smoke. 医生建议他不要抽烟.
I propose that the matter be put to the vote at once. 我提议对此问题立刻进行表决.
He proposed that Mr. O’Leary be the chairman. 他提议奥列利先生担任主席.
She suggested that I (should) be responsible for the arrangements. 她建议我来负责进行安排.
注意：与动词insist相似,动词suggest后接宾语从句时,除可用虚拟语气外,也可用陈述语气,两者的区别也是：若谓语动词所表示的情况尚未成为事实,则用虚拟语气,此时suggest通常译为“建议”；若谓语动词所表示的情况为既成事实,则要用陈述语气,此时的suggest通常译为“表明”、“认为”.比较并体会：
He suggested that we (should) stay for dinner. 他建议我们留下吃饭.
What he said suggested that he was a cheat. 他说的话表明他是个骗子.
I suggested that you had a secret understanding with him. 我觉得你与他心照不宣.
5、表示“要求”后的宾语从句
9、表示“希望”“打算”后的宾语从句
主要是指动词desire, intend后的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美语中通常省略.
She desires that he do it. 她希望他做此事.
They intended that the news (should) be suppressed. 他们打算封锁这条消息.
I desire the patient should have a bath every day. 我希望病人每天洗澡.
10、表示“指示”后的宾语从句
主要是指动词direct后的宾语从句,从句谓语由“should+动词原形”构成,其中的should在美国英语中通常可以省略.
The general directed that the prisoners should be set free. 将军指示释放那些俘虏.
（三）表语从句和同位语从句
有些名词引起的表语从句或同位语从句中,谓语动词须用动词原形或should ＋do的形式.
这些名词包括：
advice（忠告）、 decision（决定）、 demand（要求）、 desire（渴望）、 idea（想法）、
motion（提议）、 necessity（必要性）、 order（命令）、 plan（计划）、 preference（偏爱）、
proposal（建议）、 recommendation（推荐）、requirement（要求）、suggestion（建议）等.
例句13：His proposal is that we turn off TVfor half an hour every day．他建议我们每天少看半个小时的电视.
特别提示：从以上的各类从句中我们可以得到以下的推论,即当一个动词后面的宾语从句中要使用（should）＋do的虚拟语气形式时,则可推理出用法相同的一组从句.以动词advise为例：
（1）I advise that we stay and wait here．（动词后的宾语从句）
（2）It is advised that we stay here．（It is ＋动词的过去分词＋that引导的主语从句）
（3）It is advisable that we stay here．（It is ＋由该动词转换的形容词＋that引导的主语从句）
（4）My advice is that we stay here．（由该动词转换的名词后的表语从句）
（5）I offered the advice that we stay here．（由该动词转换的名词后的同位语从句）
（6）I think it advisable that we stay here．（由该动词转换的形容词作宾语补足语,it为形式宾语,真正的宾语从句中使用虚拟语气）
以上六类从句中所使用的都为（should）＋do的虚拟语气形式.
★★★wish后宾语从句用虚拟语气
一． Wish本身为现在时,后面得宾语从句如果与现在存在状态相反的愿望,从句中谓语动词采用过去时或过去进行时,遇到be动词时各人称都用were.
二． Wish本身为过去时,后面得宾语从句如果与过去存在状态相反,从句中谓语动词采用过去时,遇到be动词时各人称都用were.
三． 凡发生在谓语（wish）以前的动作,从句中的虚拟语气谓语的结构形式是过去完成时, 即had+动词过去分词或would \ could + have done.
四． 凡发生在谓语（wish）以后的动作,从句中的虚拟语气谓语的结构形式是过去将来时,即（would +动词原形）,如果用到情态动词can,各人称都用could.
五． I wish + 从句的结构还可以转换成if only+ 从句结构.If only后也要采用虚拟语气,其构成及意思与I wish + 从句完全一样.
六．从句的时态只与从句所指的时间有关,而与wish的时态无关,比较：
I wish I were not so busy. 但愿我不那样忙碌. （与现在相反）1
I wish I were [was] better looking. 要是我长得漂亮些就好了. （与现在相反）1
I wished I were rich. 当时我后悔自己没有钱. （与过去相反）2
I wished I had been rich. 当时我后悔自己曾经没有钱. （与过去相反）3
She wished she had stayed at home. 她后悔的是她当时要是留在家里就好了. （与过去相反）3
I wish you would go with us tomorrow. 要是你明天同我们一起去就好了. （与将来相反）4
I wish you wouldn’t look down on this kind of work. 我希望你不要看不起这种工作. （与将来相反）4
I wish you wouldn’t smoke any more. 我希望你不再抽烟了. （与将来相反）4
I wish you would be more respectful to your father. 我希望你对你父亲更尊敬些. （与将来相反）4
I wish I could be of some use. 我希望我能有什么用处. （与将来相反）4
If only I were you.= I wish I were you. 我要是你就好了. （与现在相反）5
★★★虚拟语气的几个特殊句型：
★★★would rather后句子用虚拟语气：would rather后接句子时,句子谓语习惯上要用虚拟语气,具体用法为：
1．一般过去时表示现在或将来的愿望
I’d rather you went tomorrow (now). 我宁愿你明天(现在)去.
I’d rather you came next Saturday. 我宁愿你下星期六来.
I’d rather you were happy. 我愿你快乐.
I’d rather she sat next to me. 我宁愿她挨着我坐.
I’d rather Jack left on an earlier train. 我宁愿杰克乘前一班火车走.
You always go without me and l’d rather you didn’t. 你总是不带我去,我可不愿意你这样.
“Shall I open the window? ” “I’d rather you didn’t. ”“我要不要把窗子打开? ” “我看不要打开好.”
2. 用过去完成时表过去的愿望
I’d rather you hadn’t said it. 我真希望你没有这样说过.
I’d rather you hadn’t done that. 我宁愿你没这样做.
l’d rather you had been / hadn’t been present.我 (宁) 愿你当时在场 / 不在场.
l’d rather he had told / hadn’t told me about it 我 (宁) 愿他告诉了 / 未告诉我这件事.
Katie went by car and I’d rather she hadn’t. 凯蒂是坐汽车去的,我宁愿地不坐汽车去.