一.概念

語氣有三種:陳述語氣,祈使語氣和虛擬語氣.其中陳述語氣和祈使語氣又稱真實(shí)語氣，語氣表示說話人對(duì)勸詞所示示的動(dòng)作或所處的狀態(tài)持有的態(tài)度或看法.

二.知識(shí)點(diǎn)精講

1.辨別if引導(dǎo)真實(shí)條件句和if引導(dǎo)的虛擬條件句的區(qū)別

If he has time, he will go with us.= Probably he has time and will go with us.

If he had time, he would go with us.=But in fact he has no time.

2.虛擬條件句中主句和從句的謂與動(dòng)詞構(gòu)成形式如下表

if條件句中的謂與動(dòng)詞

主句的謂與動(dòng)詞

與現(xiàn)在的事實(shí)相反

1.行為動(dòng)詞用did形式

2. be動(dòng)詞用were

should

would

could+動(dòng)詞原形

might

與過去的事實(shí)相反

had + done

should

would

could+ have + done

might

與將來的事實(shí)相反

1.行為動(dòng)詞用did

2. should +動(dòng)詞原形

3. were to +動(dòng)詞原形

should

would

could+動(dòng)詞原形

might

3.混合時(shí)間的虛擬語氣

如果條件句中的動(dòng)作和主句的動(dòng)作不是同時(shí)發(fā)生，主句和從句的謂語動(dòng)詞的形式應(yīng)分別根據(jù)各自所表示的時(shí)間加以調(diào)整。

1)0If I had received the passport yesterday, I would start today.

2)If he had telephoned me last night, I would see him now.

3)If he had followed the doctor’s advice, he would be all right now.

4)If China had not been liberated, the working people would still be leading a miserable life.

4.should/ could / might/ ought to + have done表示“過去本應(yīng)該/可以做而實(shí)際上卻沒做”

needn’t have done表示“過去沒必要作而實(shí)際上做了”

5.虛擬語氣中的倒裝句

如果虛擬語氣的條件從句謂語動(dòng)詞中含有were, had, could, should，有時(shí)可將if省去，而將條件從句的主語置于were, had, should, could之后。

Had you invited us, we would have come to your party.

Were I you, I would do more practice after class.

Could she lend us a helping hand, she would do so.

本文來自：逍遙右腦記憶 http://m.yy-art.cn/gaozhong/181676.html

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