表示“可能”:might, may, could, can
表示“推測(cè)”:will, would
表示“必然”:should, ought to, must
其中,might表示的可能程度最低,must表示的可能程度最高。按照可能性程度的高低程度,以上情態(tài)動(dòng)詞可以表示為:
might< may < could < can < should < ought to < would< will < must
具體而言,推測(cè)性情態(tài)動(dòng)詞具有以下句法特征:
1. 后接動(dòng)詞完成體形式:
He could have gone home. 他可能已經(jīng)回家了。
You must have worked out this question. 你一定已經(jīng)解決這個(gè)問(wèn)題了。
He might have been very sad. 他可能很傷心。
2. 后接進(jìn)行體形式:
He may be writing a letter now. 他現(xiàn)在可能在寫信。
He must be lying. 他一定在撒謊。
They must have been working these days. 這些天他們一定都在工作。
3. 后接動(dòng)詞的一般形式:
It must be Tom. 那一定是湯姆。
Lucy isn’t at home. She must be in the library. 露西不在家,她一定在圖書館。
4. 用于there be句式:
The plan isn’t approved. There must be some mistake in it.
計(jì)劃沒得以通過(guò),一定是其中出了差錯(cuò)。
There could be someone in the classroom since the lights are on.
燈開著,教室里可能有人。
“推測(cè)性”情態(tài)動(dòng)詞是英語(yǔ)中易錯(cuò)的語(yǔ)法點(diǎn),需要我們理清其用法,熟練掌握。