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动词的特殊形式表示出来的。

虚拟语气怎么用

（1） 对现在情况的虚拟

对现在情况的虚拟，条件句中谓语动词用一般过去时，主句用“would/should/might/could+动词原形”。

（2） 对过去情况的虚拟

对过去情况的虚拟，条件句中谓语动词用过去完成时，主句用“would/should/might/could+have+过去分词”。

（3） 对将来情况的虚拟

对将来情况的虚拟，条件句中谓语动词可用should do, were to do或动词的过去式三种形式表示，但意义略有不同。should表示的可能性最大，动词过去式的可能性次之，were to do的可能性最小。主句谓语动词用“would/should/might/could+动词原形”。

（4） 错综时间条件句

有时条件从句谓语动词表示的动作和主句谓语表示的动作发生的时间不一致，这类句子称为错综时间条件句。此时主从句动词的形式应根据各自所表示的时间进行调整。

If you had taken my advice then, you wouldn't be in trouble now.

如果当时听我劝，你现在就不会有麻烦了。（if条件句是对过去的虚拟，故用过去完成时，而主句是对现在的虚拟，故用“would+动词原形”形式。）

（5） 表示“建议、命令、要求、坚决做”等动词后的宾语从句常用“(should+)动词原形

（6） wish后的宾语从句

wish后的宾语从句用一般过去时表示现在的情况，用过去完成时表示过去的情况，用would/could do表示将来的情况。

（7） would rather 后的宾语从句

would rather后的从句常用一般过去时形式，表示现在或将来的情况；用过去完成时，表示过去的情况

（8）It is/was important (necessary, appropriate, proper, right, essential, vital, etc.) that

英语虚拟语气有什么用法

一.概念: 动词虚拟语气表示说话人的愿望, 假设, 猜测, 建议, 请求, 意图, 设想等未能或不可能成为事实的情况, 或者在说话人看来实现可能性很小的情况, 而不表示客观存在的现实

二.虚拟语气的表现形式: 通过句中谓语动词的特殊形式来表现. 这些特殊形式与谓语动词的某些时态相同, 但它们只表示语气, 而不表示时态, 但含有一定的时间概念

虚拟语气的用法

一.虚拟语气在简单句中的用法: 谓语动词用原形或may +动词原形

1.表示祝愿

a. Long live our country.

b. May you succeed.

c. May you be happy all your life.

2.表示命令

a. Everybody leave the room.

二.虚拟语气在非真实条件句中的用法: (使用虚拟语气的含条件句的复合句称为真实条件句)

1.表示与现在事实相反的情况时, if从句的谓语用动词的过去式 (be动词的过去式多用were, 而不用was), 主句的谓语用should / would / could / might +动词原形 (should多用于第一人称, would多用于二三人称, could / might可用于所有人称)

a. If I had more time, I should study computer better.

b. If he were not so busy, she would attend the meeting this afternoon.

c. If they didn’t take exercises every day, they wouldn’t be so healthy.

d. If you went to bed earlier, you would not be so sleepy in the morning.

e. If she invited me, I should go to the party.

2.表示与过去事实相反的情况时, if从句的谓语用had done形式, 主句的谓语用should / would / could / might + have done的形式

a. If she had invited me yesterday, I should have gone to the party.

b. I would have checked my paper again if I had had more time at yesterday’s exam.

c. If you had taken the teacher’s advice, you would not have failed in the exam.

3.表示与将来事实相反的情况时, if从句的谓语形式是: ①.完全动词过去式 (be的过去式通常用were); ②.should +动词原形; ③.were to do. 其中②, ③种情况都含有出乎意料之外之意; 主句的谓语的形式是: should / would / could / might +动词原形

a. If she should invite me tomorrow, I should go to the party.

b. If it rained / should rain / were to rain tomorrow, our picnic would be put off.

c. If I saw him tomorrow, I would pass your note to him.

d. I might come back if I were to miss the train.

三.虚拟语气在非真实条件句中用法的几个变体:

1.条件从句省略if: 在书面语中, 如果条件从句中的谓语中有were, had, should等词, 可将if省略, 而把were, had, should放在句首

a. Were I you (=If I were you ), I would get up early very early.

b. Had you arrived (=If you had arrived ) at the station ten minutes earlier yesterday, you could have caught the train.

2.省略条件从句或主句, 省略部分的含义仍有所体现. 省略主句时, 表示己不能实现的愿望

a. You could have done it yourself (if you had wanted to).

b. I wouldn’t smoke (if I were you).

c. If my old friends were with me! (要是老朋友和我在一起该多好啊)

d. If you could have seen the wonderful film!

3.主从句时间不一致时, 主从句谓语动词的形式取决于要表示的具体时间

a. You would speak English well if you had practised speaking it every day.

b. If she hadn’t trained so hard, she wouldn’t be able to run so fast.

4.假设的条件不以条件从句, 而以其他方式如介词短语、从句等表达出来, 这种句子称为含蓄条件句

a. What would you do with a million dollars?

b. Without music, the world would be a dull place.

c. We could have done better with more money.

d. He would have given you more help, but he has been so busy.

四.虚拟语气在as if / though从句中的用法:

1.表示与现在事实相反或对相在情况有所怀疑, as if / though从句谓语用过去式

a. He speaks English so well as if she had studied English in England.

b. She looked as if she were ill.

2.表示与过去事实相反的情况, as if / though从句谓语用过去完成式

a. The machines operated as if it had been repaired.

五.虚拟语气在含even if / though从句的复合句中的用法:

在此类复合句中, 若表示与事实相反, 可用虚拟语气形式. 主从句的谓语动词形式与非真实条件句相同

a. Even if I were rich, I would work.

六.虚拟语气在主语从句中的用法:

如果表示说话人的看法, 想法或意见, 在句型 It is / was + adj. + that从句中, 主语从句中可用虚拟语气. 主语从句中谓语动词用should do表示现在或将来情况, 用should have done表示过去情况

a. It is necessary that you should clean the lab before you left.

b. It is important that you should take the doctor’s advice.

c. It was very strange that he should have left without say goodbye.

七.虚拟语气在宾语从句中的用法:

1.在wish的宾语从句中, 通常表示不可能实现或没有实现的愿望, 常用虚拟语气

①.wish的宾语从句用过去式, 表示现在或将来没有实现或不可能实现的愿望

a. I wish I knew the result of the match now.

b. I wish it were spring here all the year round.

c. I wish I could help you.

d. I wish I were young.

②.wish的宾语从句用过去完成式, 表示过去没有实现或不可能实现的愿望

a. We wish we had got the film tickets last night.

b. I wish you I had met him yesterday.

③.wish的宾语从句若用would, 则一般表示请求, 对现状不满或希望未来有所改变

a. I wish the prices would come down.

b. I wish you would help me.

c. I wish he would be more careful.

d. We wish you would spend the holiday with us.

2.在动词suggest (建议), advise (建议), demand (要求), require (要求), order (命令), insist (坚持)后的宾语从句中, 谓语动词常用( should )+动词原形的虚拟语气形式

a. I suggested that we should go there at once.

b. I demand that he should answer me at once.

c. The doctor insisted that the patient should stay in bed for two weeks.

d. The officer ordered that the soldiers should stop playing.

与名词suggestion建议 / advice 建议 / demand要求 / request要求 / order命令有关的从句(包括同位语从句和表语从句等)中的谓语也用 ( should ) +动词原形

a. The black people made a strong demand that the government ( should ) take steps to change the unfair situation.

b. Their demand is that the government should take steps to change the unfair situation.

c. I was Bill’s suggestion that everybody should have a map.

d. His suggestion was that everybody should have a map.

八.虚拟语气用在句型: It is time that(该做某事了)中: that从句中的谓语动词用过去式

a. It is time we got up.

九.虚拟语气用在if only引导的感叹句中: 表示但愿, 要是就好了, 其中谓语形式与wish的宾语从句相同

a. If only he didn’t drive so fast! ( =I wish he didn’t drive so fast.)

b. If only he had taken the doctor’s advice. ( =I wish he had taken the doctor’s advice.)

c. If only the rain would stop! ( =I wish the rain would stop.)

十.虚拟语气用在would rather / prefer后的that从句中: 表示现在或将来情况谓语动词用过去时形式, 表示过去情况动词用过去完成时形式

a. I would rather he came next Saturday.

b. I would prefer you had seen the film yesterday.

c. I would rather that he painted the house blue