何时用apear to do,何时用apear to have done?分别要是什么时态背景?请举例说明,一楼，我有见过She appears to have known it.
问题描述：
何时用apear to do,何时用apear to have done?分别要是什么时态背景?请举例说明,
一楼，我有见过She appears to have known it.
答
apear to do apear to have done appear to be doing
pretend to do pretend to have done pretend to be doing
很多类似搭配，其实很简单，to do表示目前或将来，to have done表示过去货已经发生。
I think we don't have to tell her the news,for She appears to have known it.
We'd better go and help her,for She appears to be looking for something.
she appears to lose her way.Let's go and help her.
答
前者是一般现在时，而后者是过去完成时
答
这个不是时态的问题 这是个非谓语的题 因为appear这个词后要接不定式 ,但是不定式的动词和谓语动词appear有先后的问题：比如你说的She appears to have known it.这里面know这个动作发生在appear这个动作之前,所以要...