过去不可能过去没能
I saw Mr. Wang just now. he couldn’t have gone toBeijing.
May/might have done
“也许/或许已经---”一般只用于肯定句和否定句中（在否定句中表示“可能不”），不用于疑问句。用might则表示语气更加不肯定。
It’s too late. I think he may have gone to bed.
I would rather have taken his advice.
I raised objections at the meeting, but now I would rather not have done that.
Would like/love to have done
表示过去愿意做某事，但未做成。
The lights were out. They must have been asleep.
Can/could have done
本来能够过去可能会
You could have come 5 minutes earlier.
Can he have gone to his aunt’s?
Can/could not have done
You had better have started earlier.
You had better not have scolded her.
Would rather have done
表示“宁愿当时做某事”，其否定式would rather not have done表达相反的含义，两者都表示“后悔”之意。
I would love to have gone to the party last night but I had to work extra hours to finish a report.
Shouldn’t/ought not to have done
“ห้องสมุดไป่ตู้不该做而做了某事”
You shouldn’t have told her the truth.
Needn’t have done
表示“做了本来不必去做的事”注意：didn’t need to do表示“没必要做而实际上也没有做某事”。
He may not have finished the work.
She might have caught a cold.
Should/ought tohave done
“本该做某事，而实际上未做”
You should have come to the meeting earlier.
You ought to have done this exercise more carefully.
情态动词+完成时
意义
例句
Must have done表示对过去发生的事情的一种十分肯定的推测
“想必/准是/一定做了某事”，
否定式为can’t/couldn’t have done
It must have rained last night, for the road was quite muddy.
You needn’t have taken a taxi here, for it was very near to my house.
I didn’t need to clean the windows. My brother did it.
Had better have done
用于事后的建议，含轻微责备的口吻，意为“要是当时做了某事就好了”，其否定式had better not have done表达相反的含义。