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語氣，語氣表示說話人對勸詞所示示的動作或所處的狀態(tài)持有的態(tài)度或看法.

二.知識點精講

1.辨別if引導真實條件句和if引導的虛擬條件句的區(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詞構成形式如下表

if條件句中的謂與動詞

主句的謂與動詞

與現在的事實相反

1.行為動詞用did形式

2. be動詞用were

should

would

could+動詞原形

might

與過去的事實相反

had + done

should

would

could+ have + done

might

與將來的事實相反

1.行為動詞用did

2. should +動詞原形

3. were to +動詞原形

should

would

could+動詞原形

might

3.混合時間的虛擬語氣

如果條件句中的動作和主句的動作不是同時發(fā)生，主句和從句的謂語動詞的形式應分別根據各自所表示的時間加以調整。

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“過去本應該/可以做而實際上卻沒做”

needn’t have done表示“過去沒必要作而實際上做了”

5.虛擬語氣中的倒裝句

如果虛擬語氣的條件從句謂語動詞中含有were, had, could, should，有時可將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://www.yy-art.cn/gaozhong/181676.html

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