关系副词where在定语从句中也是用作状语，表示地点，用以修饰表示地点的先行词;在许多情况下也可以理解为“介词+which”的意思(which的意思与先行词所表示的意思等价)，其中的“介词”通常应根据先行词的含与搭配来确定。如：

What is the name of the town where you live? 你住的那个城市叫什么名字?

句中的where you live为修饰the town的定语从句，关系副词where在此相当于in which。表示住在某城市，英语习惯上说 live in a city，所以此处用 in which。

This cross marks the spot where she died. 这个十字符号标明她死去的地点。

句中的 where she died 为修饰 the spot 的定语从句，关系副词 where 在此相当于 at which。表示在某一地点，英语习惯上说 at a spot，所以此处用 at which。

■why的用法

关系副词why在定语从句中也是用作状语，表示原因;why引导定语从句时，其先行词只有一个，那就是the reason;在许多情况下why也可以理解为for which。如：

These are the reasons why we do it. 这些就是我们这样做的理由。

句中的why we do it为修饰the reason的定语从句，关系副词why在此相当于for which。

Do you know the reason why she doesn’t like me? 你知道她不喜欢我的原因吗?

句中的why she doesn’t like me为修饰the reason的定语从句，关系副词why在此相当于for which。

why是一个比较特殊的关系副词，它引导定语从句时，除可换成for which外，有时也可换成that，甚至省略。如：

他失去工作的主要原因是他喝酒。

正：The main reason why he lost his job was that he drank.

正：The main reason for which he lost his job was that he drank.

正：The main reason that he lost his job was that he drank.

正：The main reason he lost his job was that he drank