关于定语从句的理解

it is the room in which i used live.
这句话中 live in 中的 in 就提前到了which前面。
定语从句中，从句充当的是定语成分。这是最简单的理解

关系代词whom或which在定语从句中作介词宾语时,介词可放在后面,也可提前构成介词+关系代词whom (先行词指人)/which(先行词指物)引导定语从句(这种方法更为正式)。例:

Mary is the girl whom I borrowed a book from. = Mary is the girl from whom I borrowed a book. 玛丽就是我向她借书的那个女孩。

Is this the room that/which he once lived in? = Is this the room in which he once lived? 这是他曾经住过的房子吗?

常见的有以下几种情况:

1. where=in/on which 例:

This is the room where / in which he lives.这是他住的房间。

I can see the playground where / on which they do sports.我能看见他们进行运动的操场。

2. when= on/in/at which 例:

I still remember the year when/ in which I joined the Party.我仍然记得入党的那一年。

I still remember the day when/on which I joined the Party. 我仍然记得入党的那一天。

I still remember the hour when/at which the rocket was launched.我仍然记得那个火箭发射的时刻。

3. why=for which 例:

This