②could have done本来可以,表示未曾实现的可能性或虚拟语气。表示过去可能做某事,但没有实现。 You could have passed the exam, but you didn't study hard.你本来可以通过考试的,但你不努力学习。 If you had come yesterday, you could have seen the movie star...
when it comes to human rights, considering what the US has done historically and currently, its officials are in no position to wantonly criticize China. I wish we could ma...
除ought, used, have后跟不定式外,其他情态动词一律跟动词原形。情态动词主要有:can/could, may/might, must, ought to, used to, need, dare, shall/should, will/would, have to等。 ...
2.would have done = 本来就会去做某事而没做 3.could have done = 本可以做某事而没做 4.might have done 本可以做而没做 例:They ought to have apologized. 他们本该道歉的。 5. must have done sth 一定做过某事 否定形式:can't / couldn’t have done ...
情态动词+不定式完成式(have done) 1) can / could + have done在肯定句中表示“本来可以做而实际上能做某事”,是虚拟语气;在疑问句或否定句中表示对过去行为的怀 疑或不肯定, 表示推测。1. You could have done better, but you didn’t try your best.(虚拟语气)2...
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