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He can't have been ill是现在完成时?

来源：百度知道编辑：UC知道时间：2024/06/08 06:21:17

是现在完成时?
那可以不可以He have can't been ill?
还是必须放前面?
是猜测晓得了额,CAN'T BE..
但是不是现在完成时吗,为什么不是HAVE放前面呢?

can't have done .用于表示对过去发生的事进行猜测,不可以He have can't been ill?
首先你应该知道什么是现在完成时 have done。 can是情态动词，情态动词＋完成时和完成时本身的意义是不一样的。have后面可以加副词但不能加情态动词。

这个是情态动词加完成时表推测阿

对过去的推测

I think grammatically this is incorrect. I have never seen someone say "He can't have been ill". The proper way is "He couldn't have been ill."

He can't be at school,___? I have some trouble,that is I can't find him and he will be in danger.这里that is 对不对 .He can't be at school,____ ? A.is he B.isn't he C.can he D.can't he请帮忙解释为什么选A。 can't have been He is so inexperienced that we can't have him_the material in this way. Paul doesn't have to be made( ).He is always a hard-working student. Everyone's life may have to be short,but no reason why it can't to be beautiful he don't have any ( ) or ( ). Can't he speak English? 能否说：He can't be able to win the race if he doesn't run fast enough.是否要将can't改成won't?