用在一般虛擬條件句中的虛擬語氣

(一)表示與現(xiàn)在、過去、將來事實相反的假設

1. 與現(xiàn)在事實相反的假設。

其句子結(jié)構(gòu)為：

從句：if+主語+動詞的過去式(be變were)+其他

主句：主語+would(should, could, might)+動詞原形+其他

例：If I were you, I would go with him.

2. 與過去事實相反的假設。

其句子結(jié)構(gòu)為：

從句：If+主語+過去完成時+其他

主句：主語+should(would, could, might)+現(xiàn)在完成時+其他。例：If you had studied harder last term, you could have passed exam.

3.表示對將來事實實現(xiàn)的可能性不大的假設。

其句子結(jié)構(gòu)為：

從句：If+主語+should (were to )+動詞原形+其他

主句：主語+would (could, should, might)+動詞原形

例：If he were to go tomorrow. He might tell you.

(二)從句和主句要根據(jù)各自發(fā)所生的時間選用符合具體時間的虛擬語氣形式

1. 從句表示過去，主句表示現(xiàn)在。

If they had stared the early morning yesterday, they would be here now.

2. 從句表示將來，主句表示過去。

If I were not to make a preparation for my experiment this afternoon, I would have gone to see the film with you last night。

3. 從句表示過去，主句表示將來。

If we hadn’ t made adequate preparations, we shouldn’ t dare to do the experiment next week。

4.從句表示將來，主句表示現(xiàn)在。

If we shouldn’ t have an exam this afternoon. I would go shopping now.