虛擬語氣的用法

虛擬語氣表示說話人的愿望、假設(shè)、猜測或建議,而不表示客觀存在的事實(shí)。虛擬語氣通過謂語動詞的特殊形式來表示。下面分別介紹虛擬語氣在各種句式中的用法。

1. 虛擬語氣用于條件狀語從句

注意:主句中的should通常用于第一人稱,would可用于任何人稱,同時也可根據(jù)意思用情態(tài)動詞could, might等代替should, would。

1)表示與現(xiàn)在事實(shí)相反:

If I were you, I should stay at home.

If the peasants could farm the land themselves, food production would be much higher.

If fewer cash crops were grown, more food could be produced and there would be less or no starvation.

2)表示與過去事實(shí)相反:

If you had come yesterday, you would have met him.

If the hurricane had happened during the daytime, there would have been many deaths.

3)表示與將來事實(shí)相反:If you came tomorrow, we would have the meeting.

If it were to/should rain tomorrow, the meeting would be put off.

If it should rain, the crops would be saved.

4)當(dāng)條件狀語從句表示的行為和主句表示的行為所發(fā)生的時間不一致時,動詞的形式要根據(jù)它所表示的時間來調(diào)整。例如:If you had followed the doctor’s advice, you would be quite all right now. (從句說的是過去,主句指的是現(xiàn)在.)

5)以上句型可以轉(zhuǎn)換成下列形式:①從句省略if,用倒裝句式"were, had, should+主語"。例如:Were I in school again, I would work harder. Had you been here earlier, you would have seen him. Should there be a meeting tomorrow, I would come.②用介詞短語代替條件狀語從句。例如:Without air, there would be no living things. I would not have succeeded but for your help.

2.虛擬語氣用于賓語從句

1)"wish+賓語從句"表示不能實(shí)現(xiàn)的愿望,漢語可譯為"可惜……"、"……就好了"、"悔不該……"、"但愿……"等。表示現(xiàn)在不能實(shí)現(xiàn)的愿望,從句的謂語動詞用過去式;表示將來不能實(shí)現(xiàn)的愿望,用"would(could)+動詞原形";表示過去不能實(shí)現(xiàn)的愿望,用"had+過去分詞"或"(could)would + have + 過去分詞"。例如:

I wish we could go to the seaside today.

I wish you told me earlier.

We wish we had arrived there two hours earlier.

2)虛擬語氣在動詞arrange, command, demand, desire, insist, order, propose, request, require, suggest 等后面的賓語從句中,用"(should)+動詞原形"。例如:

I suggested that the meeting (should) be put off.

The doctor ordered that she (should) stay in bed for a few days.

They demanded that the black people should be treated as well as white people.

注意:insist作"力言"、"強(qiáng)調(diào)"解時,賓語從句不用虛擬語氣。只有當(dāng)insist作"堅(jiān)持(應(yīng)該)"解時,賓語從句才用虛擬語氣。例如:

Mike insisted that he had never stolen anything.

I insisted that you give me my money back.

3.虛擬語氣用于表語從句、同位語從句做advice, idea, order, demand, plan, proposal, suggestion, request 等名詞的表語從句和同位語從句,其謂語動詞要用虛擬語氣的結(jié)構(gòu)"(should)+動詞原形"。例如:

We all agreed to his suggestion that we (should)go to Beijing for sightseeing.

My idea is that he (should) do exercises first.

4.虛擬語氣用于以as if(as though)引導(dǎo)的表語從句或狀語從句

如果從句表示與現(xiàn)在事實(shí)相反,謂語動詞用一般過去時;表示與過去事實(shí)相反,謂語動詞用"had+過去分詞";表示與將來事實(shí)相反,謂語動詞用"would(might, could )+動詞原形"。例如:

He looked at me as if I were mad.

He speaks English so fluently as if he had studied English in England.

It looks as if it might rain.

但as if(as though)后的從句也常用陳述語氣,這是因?yàn)閺木渲械那闆r往往是可能發(fā)生的或可能被設(shè)想為真實(shí)的。例如:

It looks as if our side is going to win.

5.虛擬語氣用于主語從句

在主語從句中,謂語動詞的虛擬語氣結(jié)構(gòu)用"should+動詞原形"的結(jié)構(gòu),表示驚奇、不相信、惋惜、理應(yīng)如此等。例如:

It is necessary (important, natural, desirable, advisable, strange, etc.) that we should clean the room every day.

It was a pity (a shame, no wonder, etc.) that you should be so careless.

It will be desired (suggested, decided, ordered, requested, proposed, etc.) that she should finish her homework this afternoon.

在上述三種主語從句中,should意為"應(yīng)該"、"竟然",可以省去,但不可換用would。主句所用動詞的時態(tài)不限。

注意:這種從句表示的是事實(shí)。如果說話人對這種事實(shí)表示驚奇,就可用虛擬語氣。反之,如果不表示驚奇,that從句也可用陳述語氣。例如:

It is strange that he did not come yesterday.

It is a pity that you can’t swim.