(1) where 引导的定语从句

例：This is the house where he lived last year. 这就是他去年住过的房子。

(2) where 引导的状语从句

例：Where there is a will，there is a way．有志者事竟成。

    He left his key where he could find．他将钥匙放在易找到的地方。

    I will go where I want to go．我要去我想去的地方。

(3) where  引导的表语从句

例：This is where you are wrong.   这正是你错的地方。

注：引导状语从句的where= 介词+the place where （定语从句）

例：Go where you are most needed.到最需要你的地方去。