She was ill,She can t have attended the meeting here
题目
She was ill,She can t have attended the meeting here
为什么用can t have attended 而不用 could not be able to attend
答案
could 怎么还和be able to 连用?
can't have done sth本身表示对过去情况的否定推测,意为：“根本不可能.”
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