虛擬語(yǔ)氣是動(dòng)詞的一種特殊形式，用來(lái)表達(dá)說(shuō)話人的愿望、請(qǐng)求、意圖、建議、驚奇、設(shè)想等。虛擬語(yǔ)氣在各種結(jié)構(gòu)中的運(yùn)用是歷年三級(jí)統(tǒng)考必考的內(nèi)容，考生必須熟練掌握。以下從五個(gè)方面介紹。
一、虛擬條件句中虛擬語(yǔ)氣的運(yùn)用：
虛擬條件句從時(shí)間上又分為與現(xiàn)在事實(shí)相反，與過(guò)去事實(shí)相反，與將來(lái)事實(shí)可能相反三種情況。表示與現(xiàn)在事實(shí)相反的，if從句用過(guò)去式，主句用would （或could ,should ,might）加原形動(dòng)詞。與過(guò)去事實(shí)相反的，if從句用過(guò)去完成時(shí)，主句用would（或could ,should ,might）+have done結(jié)構(gòu)。與將來(lái)事實(shí)可能相反的，if 從句用should （或were to ）加動(dòng)詞原形，主句用would加動(dòng)詞原形。
1、If a better material _____, the strength of the part 高中語(yǔ)文 would have been increased.
A. had been used
B. had been using
C. being used
D. using
�。ǜ鶕�(jù)前面的講解，正確答案為A。） （1992年58題）
2、Had the weather been good, the children _____ out for a walk.
A. had gone
B. could have gone
C. would go
D. went
�。ù鸢福築。與過(guò)去的事實(shí)相反。當(dāng)if從句中含有were, had, should這三個(gè)詞時(shí)，if可以省略，主謂倒裝。）（2001年57題）
二、某些動(dòng)詞后的賓語(yǔ)從句以及某些名詞后的表語(yǔ)或同位語(yǔ)從句中虛擬語(yǔ)氣的運(yùn)用，這些動(dòng)詞或名詞包括：
suggest （suggestion）,propose（proposal）,advise （advice）demand, insist, order, request, require, recommend, desire, ask, decide等。在這些從句中，謂語(yǔ)形式為should加動(dòng)詞原形，should可以省略。
例：The general’s command was that the soldiers _____ their fort and carry out more important task.
A. would leave
B. leave
C. left
D. have left
�。ù鸢福築） （2002年49題）
三、在It is desired （或desirable）, It is important等結(jié)構(gòu)后面的主語(yǔ)從句中，動(dòng)詞用原形或should+原形動(dòng)詞。這些結(jié)構(gòu)有：
“It is suggested”, “It is requested”,“It was ordered”, “It is necessary”, “It is essential”, “It is vital”, “It is urgent”,“ It is impossible”, “It is preferable”, “It is advisable”, “It was proposed”等。
例：It’s desired that she _____ to teach us at least twice a week.
A. comes
B. will com
C. come
D. may come
（答案：C）（1997年29題）
四、would rather, as if/though 以及wish后邊that從句中虛擬語(yǔ)氣的運(yùn)用。
1、I am too busy these days. I would rather all of you _____ next month for a dinner.
A. come
B. would come
C. came
D. have come
�。ù鸢福篊。would rather 后面的從句中，動(dòng)詞用過(guò)去式。）（2002年46題）
2、He talks as if he _____ everything in the world.
A. knows
B. knew
C. had known
D. would have know
�。ㄕ_答案為B。在as if/though后邊的方式狀語(yǔ)從句中，表示與現(xiàn)在事實(shí)相反或?qū)ΜF(xiàn)在的情況有所懷疑，動(dòng)詞用過(guò)去式；如果表示的是中的過(guò)去的動(dòng)作，用過(guò)去完成時(shí)。本句表示對(duì)現(xiàn)在的情況有所懷疑。）（1998年45題）
3、You look as if you had seen a ghost.
�。ù司渲衋s if 后邊是說(shuō)話人想象中的動(dòng)作，所以用過(guò)去完成時(shí)。）
4、I wish I knew his address.
�。ㄔ趙ish后邊的從句中，如果指現(xiàn)在或?qū)?lái)的愿望，動(dòng)詞用過(guò)去式。這句話告訴我們說(shuō)話人并不知道他的地址。）
5、Peter wishes that he _____ law instead of literature when he was in college。
A. could study
B. studied
C. had studied
D. would study
�。ù鸢笧镃。表示過(guò)去沒(méi)有實(shí)現(xiàn)的愿望，動(dòng)詞用過(guò)去完成時(shí)。）（2000年32題）
五、在It is （high） time后邊的that從句中，動(dòng)詞用過(guò)去式，表示該做某事了。
例：Don’t you think it is time you _____ smoking?
A. give up
B. gave up
C. would give up
D. should give up
�。ù鸢笧锽。）（1999年31題）
本文來(lái)自：逍遙右腦記憶 http://www.yy-art.cn/gaozhong/62634.html
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