if引导虚拟语气三种用法，did，should do，were to do有什么区别 if在虚拟语气中三种用法的公式是什么？

if引导虚拟语气三种用法，did，should do，were to do有什么区别

if引导虚拟语气三种用法，did，should do，were to do有什么区别

did 即一般过去时,表示与当前的实际情况相反的假设,

If you were not here ,I would leave at once .要不是你在这儿,我就立即走人了.

should do 表示与将来可能的情况相反,were to do 也是如此,表示与将来可能的情况相反.

If it should rain tomorrow ,the plan would be ruined .如果明天有雨,计划就泡汤了.

虚拟语气中，were和should用法有什么区别？

区别是：

were to do和should do都可用在表示对将来情况的虚拟，但是should do 还可以用在其他的虚拟语气句式里，比如说suggest +that从句,insist+that从句中。should do还有本应该做某事却没有做，表示责备和遗憾的用法。

虚拟语气用来表示假想，而不表示客观存在的事实，所说的是一个条件，不一定是事实，或与事实相反。虚拟语气通过谓语动词的特殊形式来表示。英语中的语气分为陈述语气、祈使语气、虚拟语气三类。虚拟语气表示说话者所说的话并非事实，或难以实现的，甚至表达相反的概念。另外表示主观愿望或表达某种强烈的感情时，也用虚拟语气。

虚拟语气表示说话人的主观愿望、猜疑、建议或与事实不符的假设等，而不表示客观存在的事实。虚拟语气是由句中的谓语从句的特殊形式表示出来的。如：

If I were a bird，I would be able to fly in the air.

如果我是一只小鸟，我就能在空中飞行。

I wish I could pass the examination.

我希望我能通过考试。

May you sueed!

祝你成功！

If only we had been college students last year!

上一年我们要是大学生该多好！

虚拟语气里 had should 有什么区别

区别是用法不同。

与过去事实相反的假设。结构为：从句的谓语动词用“had + 过去分词”，主句用“should (would, could, might) + have + 过去分词”。

虚拟语气用来表示说话人所说的话并不是事实，而是一种假设、愿望、怀疑或推测。该语法主要用于if 条件状语从句中，也可用于主语从句、表语从句和宾语从句等。

虚拟语气的判断：

1. if 条件状语从句中虚拟语气的判断。if 条件状语从句有真实条件句和非真实条件句。假设条件可以实现的句子为真实条件句，反之为非真实条件句，要用虚拟语气。其形式分为以下三种：

(1) 与过去事实相反的假设。结构为：从句的谓语动词用“had + 过去分词”，主句用“should (would, could, might) + have + 过去分词”。例如：

If it had not rained so hard yesterday, we could have played tennis. 如果昨天没有下大雨，我们就能玩网球了。

(2) 与现在事实相反的假设。结构为：从句的谓语动词用过去式，系动词用were，主句的谓语用“should (would, could, might) + 动词原形”。例如：

If I were in your position, I would marry her. 如果我是你，我就娶她为妻。

(3) 与将来事实相反的假设。结构为：从句的谓语动词用“should (were to) + 动词原形”，主句用“should

(would, could, might) + 动词原形”。 例如：

If you should miss the chance, you would feel sorry for it. 如果你错过了这次机会，你会难过的。

2. 宾语从句中的虚拟语气。

(1) wish后接宾语从句中的虚拟语气：根据从句的意义来判断。

A: 表示与现在和将来事实相反的愿望，从句谓语动词用过去时态。例如：

I wish they were not so late. 要是他们来得不是这么晚就好了。

B: 表示与过去事实相反的愿望，从句谓语动词用过去完成时态。例如：

I wished he hadn't done that. 我真希望那件事不是他做的。

(2) 表示“要求、建议、命令”等动词后面的宾语从句中的虚拟语气。用于此结构的动词有：advise, direct, agree, ask, demand, decide, desire, insist, order, prefer, propose, request, suggest等。从句的谓语动词用“should + 动词原形”，其中should 可以省去。例如：

I insisted that he (should) go with us. 我坚持让他和我们一起去。

注意：当insist 表示“坚持认为”、suggest表示“表明，显示”时，不用虚拟语气。例如：

He insisted that she was honest. 他坚持认为她是诚实的。

3. 主语从句中的虚拟语气。

(1) It be + 形容词 + that... (should)...。用于该句型的形容词有：necessary, good, important, right, wrong, better, natural, proper, funny, strange, surprising等。例如：

It's natural that he should feel hurt. 他感到疼是很正常的。

(2) It be + 过去分词 ＋ that... (should)...。用于该结构中的过去分词是表示“建议、请求、命令”等词的过去分词。如： desired, suggested, requested, ordered, proposed等。例如：

It is desired that the building of the house be pleted next month. 真希望这所房子在下个月前就能竣工。

(3) It is time (about time / high time) that... + (过去时或should + 动词原形)...。例如：

It is high time I went home now. = It is high time I should go home. 我该回家了。

(4) 表语从句、同位语从句中的虚拟语气。在suggestion, proposal, order, plan, idea, advice, decision等需要具体内容解释的名词后要使用虚拟语气，其谓语动词为：should + 动词原形，连接从句的that不能省略。例如：

My suggestion is that we should go there at once. 我的建议是我们应该马上去那儿。

4． 省略形式。有时可以把含有助动词、情态动词、be或have的虚拟条件句中的连词if 省去，而将had, should, were 等词提到主语之前，即用倒装结构。这时，如果出现not等否定词时需放在主语后面。例如：

If she had been here five minutes earlier she would have seen her old friend. → Had she been here five minutes earlier she would have seen her old friend. 如果她早到五分钟，她就会看见她的老朋友了。

英语虚拟语气 if条件从句，与将来事实相反，从句用did ,were to do,should do.有什么区别？谢谢

与将来事实相反的虚拟语气，从句用 should do或were to do。 不用did。

if引导条件状语虚拟语气的三种用法

有三种情况：

（1）对过去,从句had done主句would/could/might/have done

（2）对现在,从句：did /were主句：would/could/might do

（3）对将来,should do/were to do/did.从句,更上一个一样.注意,“主将从现”原则.

关于to do引导虚拟语气

would have done -would have been done

be pleased to do -be pleased to be done

虚拟语气？

关于虚拟语气should would could 用法及区别

不能。should用在if从句中，是表示与将来事实相反的事情。

虚拟语气用wish和wished有什么区别?

wish是现在希望

wished是过去希望

I wish I had told her the truth yesterday.我现在希望昨天做某事，从句用过去完成时，表示对过去动作的虚拟假设。

At that time I wished I were a doctor.这个是那时希望，那时是个医生。是在同一个时间表示希望，用一般过去时表示当时的希望。

（当时我真希望我是一个医师。）

He wished he had learned Chinese before he came to China.这个是过去希望，在过去的过去能好学中文。

（他希望他来中国之前先学了中文就好了。）

If引导的虚拟语气有几种形式，主句和从句分别是什么

虚拟语气

虚拟语气(Subjunctive Mood)这一语法项目是各类英语考试中心测试的重点之一。虚拟语气是一种特殊的动词形式，用来表示说话人所说的话并不是事实，而是一种假设、愿望、怀疑或推测。

Ⅰ用以表示虚拟条件的虚拟语气

⒈ 用if条件从句表示的虚拟条件，是虚拟条件最普通的方式。

① 虚拟现在时表示与现在事实相反的假设，其if 从句的谓语形式用动词的过去式(be 一般用were)，主句用would/ should/ could/ might +动词原形，例如：If I were in your position I would marry her.

② 虚拟过去时是表示与过去事实相反的假设，if 从句的谓语形式用过去完成时即had＋过去分词，主句用would / should / could / might + have +过去分词，例如：If it had not rained so hard yesterday we could have played tennis.

③ 大多数的虚拟条件句属于上面三种情况的一种，但并不排除存在条件和后果中，一个和现在情况相反，另一个和过去情况相反，例如：If you had followed what the doctor said, you would not have been so painful now.这个句子在高中出现频率颇高。

④ 但是，如果后果用了虚拟语气，而条件却用陈述语气，这种用法是错的。

⒉ 除了表示虚假条件外，if从句还可以表示对将来的推测，由于是将来还没有发生的，所以谈不上是真实的还是虚假的，只能说这个事情发生的可能性有多大。一般情况下，可以用陈述语气的if从句来表示对一个未来事实的推测，这个事实是完全可能发生的。If从句的谓语形式用一般过去式或用were to / should +动词原形，主句用would / should /could/ might +动词原形，例如：Jean doesn't want to work right away because she thinks that if she were to get a job she probably wouldn't be able to see her friends very often.（1996年1月四级第44题）

⒊ 有时可以把含有助动词、情态动词、be或have的虚拟条件句中的连词if 省去，而将had , should, were 等词提到主语之前，即用倒装结构,这时候，如果出现not等否定词，否定词需放在主语后面。这种结构在口语中很少使用，但频频出现在各类考试中出现，例如：If it had not rained so hard yesterday we could have played tennis.→Had it not rained so hard yesterday, we could have played tennis.

⒋ 大多数的虚拟条件通过上面所讲的两种方法表达，但在个别句子中也可以通过介词without和介词短语but for表达，副词otherwise等表达出来。例如：We didn't know his telephone number; otherwise we would have telephoned him.（1995年6月四级第46题）值得注意的是，包含but for的句子，谓语动词必定要用虚拟形式，但包含without等短语的句子，谓语动词未必一定要用虚拟语气。

⒌ 有时虚拟条件不是明确地表达出来，而在蕴含在用but引导的从句里，于是便出现了有谓语动词是虚拟语气的主句加上谓语动词是陈述语气的but从句构成的并列复合句，例如I would have hung you but the telephone was out of order.在这样的句子里，如果主句没有用虚拟语气，或者从句用了虚拟语气，都是错的。

Ⅱ用在宾语从句中的虚拟语气

⒈ 在表示愿望的动词wish后的宾语从句中，需用虚拟语气。（wish后的that 常省略），根据主句时态，从句谓语时态相应退后一位，例如：How she wished his family could go with him.

⒉ 在具有愿望、请求、建议、命令等主观意愿的动词(desire, demand, advice, insist, require, suggest, propose, order, recommend, decide …) 后的宾语从句中需用虚拟语气。谓语动词用(should) +动词原形。值得注意的是，如果宾语从句的动词是否定的，否定词not的位置应在动词之前，而不是动词之后。例如：The head nurse insisted that the patient not be move.另外，如suggest表达“暗示”，insist表示“坚持某种说法”时，后面的从句不用虚拟语气，例如：Her pale face suggests that she is ill.或He insisted that he did not kill the boy.

除此之外，上述动词也要求用虚拟式

① 在It is+上述动词的过去分词，其后所跟的主语从句中，如It is suggested that pupils wear school uniforms.

② 在上述动词相应的名词形式作主语+连系动词，其后的表语从句中，例如His suggestion was that classed be re-scheduled.

③ 在对上述动词相应的名词进行解释的同位语从句中，如：The workers raised the demand that their pay be increased to cope with the inflation.

⒊ would （had）rather , would sooner也用来表达主观愿望，它们之后的宾语从句中需用虚拟语气。谓语动词用过去式表示现在或将来，用过去完成式表示与过去事实相反，例如：I would rather he went right now.

Ⅲ其他形式的虚拟语气

⒈ it is +necessary等形容词后，that主语从句中虚拟形式使用，这类形容词包括necessary, important, essential, imperative, urgent, preferable, vital, advisable等，例如It is necessary that you listen to the teacher carefully.或者It is essential that you be able to pronounce every single word correctly.

⒉ 在It's (high/about) time 之后的定语从句中需用虚拟语气。谓语动词用过去式，例如It is high time that you went to school

⒊ 虚拟语气在as if / as though 引导的方式状语从句中的应用（谓语动词形式与wish后的宾语从句基本相同）表示与现在事实相反或对现在情况有怀疑，谓语动词用过去式。例如：He felt as if he alone were responsible for what had happened. 表示过去想象中的动作或情况，谓语动词用过去完成式。

⒋ 在lest 引导的状语从句中，谓语动词多用虚拟语气，(should )+ 动词原形。例如： The mad man was put in the soft-padded cell lest he injure himself.（1998年1月四级第38题）

⒌ 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。例如： Look at the terrible situation I am in! if only I had followed your advice.

if在虚拟语气中三种用法的公式是什么？

我是英语专业的，或许能帮助你： 楼主记得给分~！！虚拟语气是一种特殊的动词形式，用来表示说话人所说的话并不是事实，而是一种假设、愿望、怀疑或推测。判断是真实条件句还是非真实条件句。只有在非真实条件句中才使用虚拟语气。通过句子意思，看假设的条件是否能够实现，能够实现是真实条件句，不能使用虚拟语气；假设的条件不能实现则是非真实条件句，要用虚拟语气.判断这个假设是与哪个事实相反。通常有三种情况：①与过去事实相反。②与现在事实相反。③与将来事实可能相反。

I: 最基本的虚拟语气句型:

1. 虚拟现在时表示与现在事实相反的假设，其if 从句的谓语形式用动词的过去式(be 一般用were)，主句用would/ should/ could/ might +动词原形。If places were alike, there would be little need for geographers.如果各个地方都一样，就不需要地理学家了。

2. 虚拟过去时是表示与过去事实相反的假设，if 从句的谓语形式用过去完成时即had＋过去分词，主句用would / should / could / might + have +过去分词。If he had known your address yesterday,he would have telephoned you.

3. 虚拟将来时是表示对将来实现的可能性很小的或不确定的假设。If从句的谓语形式用一般过去式或用were to / should +动词原形，主句用would / should/could/ might +动词原形。If he were to leave today, he would get there by Friday

4. 省略if 采用倒装语序的条件句。有时可以把含有助动词、情态动词、be或have的虚拟条件句中的连词if省去，而将had , should, were 等词提到主语之前，即用倒装结构。If he had worked harder, he would have got through the exams.==>Had he worked harder, he would have got through the exams.If he were to leave today, he would get there by Friday.==>Were he to leave today, he would get there by Friday.If I were in your place, I wouldn’t do that.==>Were I in your place, I wouldn’t do that.

5. 有时虚拟条件句并没用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。如：We didn't know his telephone number; otherwise we would have telephoned him. Without you help, I wouldn’t have achieved so much. But for （“要不是......”的意思）your help, I would not have succeeded.

II: 虚拟语气在从句中用should的情况:

1. 在表示建议,要求,命令,想法的动词后的从句里, 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.

His doctor suggested that he (should) take short leave of absence.

The author proposed that TV (should) be turned off at least one hour every day.

2. 在表示建议,要求,命令,想法的名词后的从句里, 用should + 动词原形, should可以省略. 如 advice, decision,agreement, command, decree, demand, determination, indication, insistence, order, preference, proposal, request, requirement, stipulation etc.

It was Bill’s suggestion that everyone (should) have a map.

His suggestion was that everyone (should) have a map.

He gave us a suggestion that everyone (should) have a map.

3. 在It is/was +形容词后的that 从句中用should的结构, should 可以省略. 这类形容词常见的有: advisable, anxious, compulsory, crucial, desirable, eager, essential, fitting, imperative(绝对必要), impossible, improper, important, natural, necessary, obligatory, possible, preferable, probable, recommended, urgent, vital etc.

It‘s natural that she (should) do so.

It is essential that we (should) tell her the news.

4. 在 lest 和 for fear that(以免),in case(以防)从句中用should, should 可以省略.

She walked quietly lest she (should) wake up her roommates.

Have your gun ready in case we should need it.

III: wish 后的 that 从句中:

1. 表示现在或将来的愿望,从句中过去式.

I wish I knew his address.

I wish I were young.

2. 表示过去没有实现或不可能实现的愿望, 从句用过去完成式或would, could, might + have + 过去分词.

I wish you had written to him.

I wish I could have slept longer this morning, but I had to get up and come to class.

3. 如果将wish改成wished, 其后that 从句中动词的形式不变.

4. 如果that 从句中用would , 一般表示 对现状不满或希望未来有所改变或请求

I wish he would answer my letter.

I wish prices would come down.

I wish you would help me.

I wish you would stop asking silly questions.

IV: 在 It’s about/ high/ first(second, third etc)time 后的that 从句中,用过去式.表示“该是做什么的时候了”

It is about time you were in bed.

It is high time we left.

It is the first time I came here.

V: 在would rather, would sooner, would just as soon 后的that从句中,用过去式或过去完成式,表示“宁愿做什么”

I would rather he came tomorrow than today.

John would rather that she had not gone to the party yesterday evening.

VI: 在if only（“如果....就好了”的意思） 感叹句中,谓语动词与wish宾语从句的虚拟形式相同.

If only he didn’t drive so fast!(现在)

If only she had asked someone’s advice.(过去)

If only the rain would stop.(将来)

VII: 在as if / as though 从句中,表示和现在事实相反或对现在情况有所怀疑,用过去式;表示过去想象中的动作或情况, 用过去完成式.

He speaks as if he were on the spot.

She spoke to me as if I were deaf.

This device operated as though it had been repaired.

注: 1. 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.

2. 在 insist 后的从句中, 如果是坚持自己, 用陈述语气, 坚持别人做什么事情, 用虚拟语气.

She insists that she is right.

She insisted that I should finish the work at once.

if虚拟语气的用法归纳

if虚拟语气的用法归纳如下：

一、表示与现在事实相反的情况：

1、从句：If主语过去时（Be动词用were）。

2、主句：主语 should/would/could/might do。

3、例句：

（1）If I were you，I would take an umbrella.

如果我是你，我会带把伞。(事实：我不可能是你）。

（2）If I knew his telephone number，I would tell you.

如果我知道他的电话号码，我就会告诉你。（事实：不知道）。

（3）If there were no air or water，there would be no living things on the earth.

如果没有水和空气，地球上就不会有生物。(事实：地球上既有空气也有水）。

二、表示与过去事实相反的情况：

1、从句：If主语had done。

2、主句：主语should/would/could/might have done。

3、例句：

（1）If I had got there earlier，I should/could have met her.

如果我早到那儿，我就会见到她。（事实：去晚了）。

（2）If he had taken my advice，he would not have made such a mistake.

如果他听我的劝告的话，就不会犯这样的错误了。（事实：没有听我的话）。

三、表示对将来情况的主观推测主句：

1、主语：should do。

2、从句：

（1）if主语：were to do。

（2）if主语：should/would/could/might do。

（3）if主语：did（动词过去式）/were。

3、例句：

（1）If he should come here tomorrow,I would talk to him.

如果他明天来这儿的话，我就跟他谈谈。(事实：来的可能性很小）。

（2）If there were a heavy snow next Sunday,we would not go skating.

如果下周日下大雪，我们就不能去滑冰了。(事实：下雪可能性很小）。

四、有时虚拟条件句中，结果主句和条件从句的谓语动作若不是同时发生时，虚拟语气的形式应作相应的调整。这种条件句叫错综条件句。

1、从句的动作与过去事实相反，而主句的动作与现在或现在正在发生的事实不符。

2、例句：

（1）If I had worked hard at school，I would be anengineer，too.

如果我在学校学习刻苦的话，我现在也会成为一个工程师了。

（2）If they had informed us，we would not come here now.

如果他们通知过我们的话，我们现在就不会来这里了。

3、从句的动作与现在事实相反，而主句的动作与过去事实不符，如：

（1）If he were free today，we would have sent him to Beijing.

如果他今天有空的话，我们会已经派他去北京了。

（2）If he knew her，he would have greeted her.

要是他认识她的话，他肯定会去问候她了。

五、当虚拟条件句的谓语动词含有were、should、had时，if可以省略，这时条件从句要用倒装语序，即把were、should、had等词置于句首，这种多用于书面语，如：

（1）Should he agree to go there，we would send him there.

要是他答应去的话，我们就派他去。

（2）Were she here，she would agree with us.

如果她在这儿的话，她会同意我们的。

（3）Had he learnt about computers，we would have hired him to work here.

如果他懂一些电脑知识的话，我们已经聘用他来这里工作了。

if引导的虚拟语气应该用什么时态

表示与现在事实相反的情况，其句型为“ if+ 主语 + 动词的过去式（ be 动词用 were ），主语 +would / could / might / should + 动词原形”。如： If the weather were fine, we would go to Shanghai.如果天气好，我们就去上海。（事实上天气不好）

表示与过去事实相反的情况。其句型为“ if + 主语 + 动词的过去完成式，主语 +would / could / should / might + have + 动词的过去分词”。如： If I had taken his advice, I shouldn't / wouldn't / couldn't have made such a mistake. 如果我按照他的建议去做，我一定不会（不可能）犯这样的错误。?

表示与将来事实可能相反的假设和结果，其句型为“ if + 主语 + 动词的过去式 / should + 动词原形 / were to +动词原形，主语 +would / could / might / should + 动词原形”。如： The glass would break if you dropped it. 杯子摔下来会打破的。（事实上没有摔下来）?

虚拟语气用来表示假想，而不表示客观存在的事实，所说的是一个条件，不一定是事实，或与事实相反。虚拟语气通过谓语动词的特殊形式来表示。英语中的语气分为陈述语气、祈使语气、虚拟语气三类。虚拟语气表示说话者做出的假设并非事实，或难以实现的，甚至表达相反的概念。另外表示主观愿望或表达某种强烈的感情时，也用虚拟语气。

在表示假想的虚假的、与事实相反的或难以实现的情况时用虚拟语气，表示主观愿望或某种强烈情感时，也用虚拟语气。即当一个人说话时欲强调其所说的话是基于自己的主观想法，愿望，假想，猜测，怀疑或建议，而不是根据客观实际，就用虚拟语气。主要是英语语法的一种表达。

条件句可分为两类，一类为真实条件句，一类为非真实条件句。非真实条件句表示的是假设或实际可能性不大的甚至完全不可能发生的情况，故采用虚拟语气。

if引导的虚拟语气

if从句的虚拟语气原理：

1、如果句子在想象现在发生而实际未发生的事件，由现在时倒退成过去时：

（从句）if+过去时，（主句）4个情态动词+动词原形

2、如果句子在想象将来发生而实际不会发生的事件，由将来时倒退成过去时，所以与1是一样的，但是此处从句有三种：

（从句）if+过去时/if+were to do/if+should do，（主句）4个情态动词+动词原形

3、如果句子在想象过去发生而实际没有发生的事件，有过去时倒退成过去完成时：

（从句）if+过去完成时，（主句）4个情态动词+have done

扩展资料

发音：英 [?f] ；美 [?f]?

释义

1、conj. （表条件）如果；即使；是否；（表假设）假如

①(表示条件)如果

②(表示虚拟)假如,要是

③(表示让步)即使

④是否

⑤(表示因果关系)每一次...的时候(总是会)

2、n. 条件；设想

参考资料：

百度百科-if

if虚拟语气的三种时态是什么?

?if虚拟语气的三种时态如下：

1、对目前状况的虚拟

条件从句中谓语动词用一般过去时，主句用“would/should/might/could+动词原形”方式，表明对目前不太可能实现状况的幻想。

If I were you,I would choose to work in a small town.

假如我是你，我会选择在小城镇工作。（实际上我不会是你）

2、对过去状况的虚拟

条件从句中谓语动词用过去完成式，主语用“would/could/should/might+have+动词的过去分词”方式。

If it had not been for your help yesterday,I could not have caught the bus.

假如昨日没有你的协助，我不会赶上公交车。（客观事实是你昨日已协助了我，因此我赶上了车)

3、对未来状况的虚拟

在表明和未来客观事实反过来的条件从句中，谓语动词可用should do,were to do或者动词的过去时三种形式表明，但是意义略有不一样。should表明的可能性最大，动词过去时的可能性其次，were to do 的可能性最小。

If things were to be twice，all would be wise.

如果任何事都能从新做一次，每个人皆可变成聪明的人。（客观事实是不是全部的事都能从新做一次)

好了，今天关于“虚拟语气if的三种用法”的话题就讲到这里了。希望大家能够对“虚拟语气if的三种用法”有更深入的认识，并且从我的回答中得到一些帮助。