tom has changed a lot .he is no longer like___ a.

题目

tom has changed a lot .he is no longer like___ a.
what he used to be
b.that he used to be
c.what he is used to be
d.that he is used to be
正确答案是a,老师说b选项后面缺少什么,缺少了什么呢?
楼下的,说一下如果我要选b应该在后面加什么,举个例子吧!
恶…我知道应该选a,理由也知道,我只是想知道如果一定要用b的话,应该在b后面加什么?
还有楼下说的重复是什么意思?哪里重复了?that相当于空气的话变成he used to be 这样到底是哪里不行了呢?

答案

或者说：tom has change a lot.he is no longer like what,he use to be.这句话的意思是,tom变了很多,不像他以前那样啦,那个what就是指他以前的状态（以前那样）.而that是不充当成分的,你可以说he is no longer like...