虛擬語態(tài)的用法如何使用虛擬語態(tài)

　　虛擬語氣在各種結(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。以下是由學(xué)習(xí)啦小編整理關(guān)于虛擬語態(tài)的用法的內(nèi)容，希望大家喜歡!

　　虛擬語態(tài)的用法

　　一、虛擬條件句中虛擬語氣的運(yùn)用：

　　虛擬條件句從時(shí)間上又分為與現(xiàn)在事實(shí)相反，與過去事實(shí)相反，與將來事實(shí)可能相反三種情況。表示與現(xiàn)在事實(shí)相反的，if從句用過去式，主句用would (或could ,should ,might)加原形動(dòng)詞。與過去事實(shí)相反的，if從句用過去完成時(shí)，主句用would(或could ,should ,might)+have done結(jié)構(gòu)。與將來事實(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 would have been increased.

　　A. had been used

　　B. had been using

　　C. being used

　　D. using

　　(根據(jù)前面的講解，正確答案為A。)

　　2、Had the weather been good, the children _____ out for a walk.

　　A. had gone

　　B. could have gone

　　C. would go

　　D. went

　　(答案：B。與過去的事實(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。)

　　二、某些動(dòng)詞后的賓語從句以及某些名詞后的表語或同位語從句中虛擬語氣的運(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

　　(答案：B)

　　三、在It is desired (或desirable), It is important等結(jié)構(gòu)后面的主語從句中，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)