这两个词主要是在定语从句在的区分,which 是关系代词,在从句中作主语、宾语,where是关系副词,在从句中作状语；如：This is the factory ______ he visited yesterday.This is the factory ______ he worked last yea...This is the house ______ was built three years ago这个句子中是用which 还是 where?用which，因为把先行词house 代入从句中为The house was built three years ago. the house 作主语，故用which，另外在定语从句中which 是先行词的意思，不解释“哪一个”，同样where 也不解释“哪里”，而是“在那个地方”