thereasonwhy…和thereasonwhich…的区别。谢谢。

the reason why+结构完整句子；例子：The reason why he was late was that he got up late.他迟到的原因是他起床晚了。the reason for which+结构完整句子；例子：The reason for which he was late was that he got up late.他迟到的原因是他起床晚了。the reason which/that+缺少主语或宾语的句子，（因为引导词作主语或宾语）例子：The reason which/that he gave can not be beileved. 他说的理由不能相信。