虛擬語氣是一種動(dòng)詞形式，表示說話人的一種愿望，假設(shè)，懷疑，猜測(cè)，建議等含義，虛擬語氣所表示的含義不是客觀存在的事實(shí)。

　　If I were you, I'd take them away. 如果我是你的話，我就會(huì)帶走他們。

　　If I had met Li Hua, I could had told him. 如果我碰見了李華，我就告訴他了。

　　If I had time. I could come to help you. 如果我有時(shí)間，我會(huì)來幫助你的。

　　He suggested that our class should be divided into five groups. 他建議說我們的班應(yīng)該分成五個(gè)小組。

　　He speaks to us as if he had been there. 他給我們講的好象他去過那兒。

　　虛擬語氣的用法：

　　一. 虛擬語氣用在簡單句中，表示祝愿，命令。

　　May you be happy. 祝你幸福。

　　May you have a good time. 祝愿你玩的痛快。

　　May the friendship between us last long. 祝愿我們的友情天長地久。

　　Have a good journey! 祝愿你旅途愉快！

　　You go out！ 你出去！

　　二. 虛擬語氣用在賓語從句中。

　　動(dòng)詞 suggest, order, insist, propose, require, request, recommend, command, desire,等詞后面的賓語從句表示的是一種虛擬語氣，賓語從句中的動(dòng)詞動(dòng)作表示的只是一種愿望、要求。

　　He insisted that all of us should be there on time by any means.

　　他堅(jiān)持要我們大家想盡辦法按時(shí)去那兒。

　　動(dòng)詞 demand, suggest, order, insist, propose, require, request, recommend, command, desire,等后面的從句中，"should" 可以省略。

　　The teacher suggested that we (should) clean the blackboard after class.

　　老師建議我們課后把黑板擦了。

　　He ordered that the students wash the clothes every week by themselves.

　　他要求學(xué)生每周都要自己洗衣服。

　　He asked that he be given an opportunity to try.

　　他要求給他一個(gè)試試的機(jī)會(huì)。

　　三. 虛擬語氣用在主語從句中。

　　在句型 "It is important (necessary, strange, natural，desired, requested, ordered, 等) that .... " 中，that 后面的從句中的謂語動(dòng)詞用： should + 動(dòng)詞原形

　　It's necessary that we should have a walk now.

　　我們有必要出去散散步。

　　It's natural that she should do so. 她這樣做是很自然的。

　　It's important that we should take good care of the patient.

　　重要的是我們要照顧好病人。

　　It is desired that we (should) get everything ready by tonight.

　　四. 虛擬語氣在表語從句和同位語從句中

　　suggestion, motion, proposal, order, recommendation, plan, idea, 等后面的表語從句和同位語從句。

　　My suggestion is that we (should) send a few people to help the other group.

　　我的建議是我們派幾個(gè)人去幫相別的小組。

　　His sole requirement is (was) that the system be adjusted.

　　他唯一的要求是把這個(gè)體系做些調(diào)整。

　　The orders were that we stay where we were.

　　命令是我們?nèi)粤粼谠�處�?

　　練習(xí)題：

　　1 . The secretary suggested that they ____ the men in at once.

　　A. had brought B. should have brought C. brought D. bring

　　2. The Jade Emperor ordered that the Monkey King _____ right away.

　　A. would be arrested B. must be arrested C. be arrested D. had to be arrested

　　3. Jane's uncle insisted ____ in this hotel any longer.

　　A. not staying B. not to stay C. that he not stay D. staying not

　　4. He demanded that the laboratory report ___ immediately after the experiment was done.

　　A. was written B. be written C. must be written D. would be written

　　5. It is required that you ____ at six.

　　A. will arrive B. arrive C. arrived D. would arrive

　　6. It is really strange that the girl ___ so early.

　　A. has been married B. has married C. be married D. would marry

　　7. The teacher agreed to the suggestion that the students ___ two weeks to prepare for the exam.

　　A. give B. should give C. be given D. would be given

　　8. It is important that I ___ with Mr. Williams immediately.

　　A. speak B. spoke C. will speak D. to speak

　　9. It is imperative that you ___ on time.

　　A. are B. will be C. be D. would be

　　10. I recommended that the student ___ his composition as soon as possible.

　　A. finishing writing B. should finish the writing C. finish writing D. finished writing

　　11. The Law requires that everyone ___ his car checked at least once a year.

　　A. has B. had C. have D. will have

　　12. The professor gave orders that the test _____________ before six o’clock.

　　A. be finished B. will finish C. will be finished D. shall finish

　　13. It is appropriate that more time ________________ to thorough study of the scheme.

　　A. should have been devoted B. ought to be devoted

　　C. must be devoted D. be devoted.

　　14. We are all for your proposal that the discussion ______________.

　　A. be put off B. was put off C. should put off D. is to put off

　　15. We strongly urge that you _______________ interfere in this matter.

　　A. don’t B. won’t C. not D. are not going to

        1.D 2.C 3.C 4.B 5.B 6.C 7.C 8.A 9.C 10.C 11.C 12. A 13.D 14.A 15.C