定语从句do you know the reason why he didn't come?why为什么可以用For which代替用which的话后面一定要缺成分,而用why后面则不缺成分.两者不矛盾了吗?

定语从句do you know the reason why he didn't come?why为什么可以用For which代替用which的话后面一定要缺成分,而用why后面则不缺成分.两者不矛盾了吗?
定语从句do you know the reason why he didn't come?why为什么可以用For which代替用which的话后面一定
要缺成分,而用why后面则不缺成分.两者不矛盾了吗?

定语从句do you know the reason why he didn't come?why为什么可以用For which代替用which的话后面一定要缺成分,而用why后面则不缺成分.两者不矛盾了吗?
Do you know the reason why he didn't come?===Do you know the reason for which he didn't come?
语法：
the reason why==the reason for which

Do you know the reason why he didn't come?与Do you know the reason for which he didn't come? 是等价的

孩子，用why骑士也是缺成分的，缺的是原因状语。如果定语从句的关系前面已经给出for,那后面的从句缺的就是介词for的宾语，因此用which,也就形成了why=for which的这一语法点。为什么给出for缺的就是他的宾语呢？主句的for怎么和后面从句缺的成分扯上关系了？for 不是主句的成分，主句的主谓宾已经全部都有了。它是从句的介词，正常应该是he didn't come for some ...

全部展开

孩子，用why骑士也是缺成分的，缺的是原因状语。如果定语从句的关系前面已经给出for,那后面的从句缺的就是介词for的宾语，因此用which,也就形成了why=for which的这一语法点。

收起