which 和 where 都可以引导定语从句，两者的主要区别在于：
一、which 是关系代词，传统上引导非限制性定语从句，在从句中指代一个人或事物，例如：
The festival, which lasted all day, ended with fireworks.
这个持续了一整天的节日以烟火结束。
He has missed his bus, which means he is going to be late.
他错过了公共汽车，这意味着他要迟到了。
二、where 是关系副词，不是关系代词，可以引导限制性和非限制性定语从句，在从句中指代一个地方，例如：
The corner store, where we usually buy our food, was robbed.
我们通常买食物的街角商店被抢了。
This is the place where Lady Elizabeth was killed by highwaymen.
这就是伊丽莎白夫人被强盗*害的地方。
Baker Street is the street where Sherlock Holmes lived.
贝克街是福尔摩斯居住的街道。
We first met him in London, where we lived in the early eighties.
我们第一次见到他是在伦敦，我们80年代初住在那里。
There is a site on the internet where you can download Classic movies.
在因特网上有一个网站，你可以在那里下载经典电影。
Though he never married her, he built her a house where she lived and raised their son.
虽然他从未娶过她，但他给她盖了一所房子，让她在那里生活，并养育了他们的儿子。
三、两者的区别
which 是关系代词，在定语从句中指代一个人或事物，主要引导非限制性从句，而 where 是关系副词，在定语从句中指代一个地点，可以引导非限制性和限制性定语从句。
