They can’t have been doing their homework ---doing是什么词性?have
They can’t have been doing their homework ---doing是什么词性?have
They can't have been doing their homework
They have been doing their homework
They can’t have been doing their homework,能不能改成下面句子
They can't have been doing thier homework.have been 是现在完成时,但
what have they been doing 是什么时态
They have finished doing their homework(改写句子)
Don't have your children______for hours doing their homework
they don't doing their homework now.
They have finished doing their homework.Their homework _ _ _
have been doing是什么时态?
have been doing sth