时间、地点或理由的名词的 先行词 是关系副词,在从句中作 状语 。
1)when, where,why
关系副词when, where, why的含义相当于"介词+ which"结构,因此常常和"介词+ which"结构交替使用.
There are occasions when (on which) one must yield.
任何人都有不得不屈服的时候。
Beijing is the place where (in which) I was born.
北京是我的出生地。
Is this the reason why (for which) he refused our offer?
这就是他拒绝我们帮助他的理由吗?
2)that代替 关系副词
that可以用于表示时间、地点、方式、理由的名词后取代when, where, why和"介词+ which"引导的定语从 句,在非正式文体中that常被省略(正式文体中不可省略),例如:
His father died the year (that / when / in which) he was born.
他父亲在他出生那年逝世了。
He is unlikely to find the place (that / where / in which) he lived forty years ago.
他不太可能找到他四十 年前居住过的地方