关于定语从句中，介词＋关系代词＋不定式的结构

英语中“介词＋关系代词”引导定语从句的现象很多，同时也较复杂，必须多加注
意。其要点如下：

1．在定语从句中，当关系代词作介词的宾语时，可以把介词移到关系代词的前面；但为
了使关系代词紧跟它所修饰的先行词，也可以把介词放在从句中有关动词的后面
。如：This is the room in which we lived last year
．（或：This is the room which we lived in last year．）
这就是我们去年居住的房子。

Who's the comrade with whom you just shook hands？
（或：Who's the comrade whom you just shook hands with？）
你刚才和他握手的那个人是谁？

2．“介词＋关系代词”结构中的关系代词只能用whom或which，不可用that。

如：The old Olympic Games from which the modern games came began around the year 776 BC in Greece ．
古代奥运会于公元前776年开始于希腊，现代奥运会就起源于那里。

What did the football player to whom you were talking want？
你刚才和他谈话的那个足球运动员想要什么？

This is the ring on which she spent 1，000 dollars．
这就是她花1000美元买的那枚戒指。

当介词跟在动词之后，不前移时，关系代词可以用that。

The pencil with which he was writing broke ．（＝The pencil which ／that he was writing with
broke ．）他写字用的铅笔折了。

The competitor to whom I was talking yesterday won the game ．（＝The competitor whom
／that I was talking to yesterday won the game
．我昨天和他谈话的那个选手赢得了比赛。

3．“介词＋关系代词”结构在定语从句中可以作状语；并可以修饰别的名词一同作状语，
此时的关系代词在定语从句中作定语。

如：I called him by the wrong name ，for which mistake I apologized．我叫错了他的名字，为此我向他表示了歉意。（定语）

He works in a middle school，in front of which there is a river．他在一所中学工作，中学前面有
一条河。（状语）

He spent four years in college ，during which time he studied medicine
．他上了四年大学，这期间他学了医学。（定语）

4．含有介词的短语动词一般不拆开，即不能转化成“介词＋关系代词”结构，介词仍放在动词
的后面。
如：Is this the book which she was looking for？
这是她在寻找的那本书吗？（不说…for which she was looking）

The babies whom the nurses are looking after are very healthy．
保育员们照看的那些孩子们很健康。（不说…after whom the nurses are looking）

This is the girl whom he will take care of．这就是他要照看的那个女孩。（不说
…of whom he will take care）

5．“介词＋关系代词”后接不定式短语作后置定语，相当于一个定语从句

如：Allow me half an hour in which to wash the clothes．＝
Allow me half an hour in which I can wash the clothes．）
给我半小时洗洗衣服。

He has a knife with which to defend himself．（＝He has a knife with which he can defend himself．）
他有一把用于自卫的刀子。

6．在下列两种情况下，介词不能前移，要放在原来的位置上。
①在关系代词that引导的定语从句中；

②在没有关系代词的定语从句中。

如：The two novels that she is fond of are written by an American writer．
她喜欢的这两本小说是一位美国作家写的。

This is the room we lived in last year．
这就是我们去年住的那个房间。

7．关系副词when，where，why有时可以转化为“介词＋关系代词which”结构。
如：I still remember the day when（＝on which）
I first came to Beijing ．
我还记得第一次来北京的那一天。
The factory where（＝in which）
his father works is in the west of the city．
他父亲工作的那个工厂在城西。

The reason why（＝for which）he is always late for class is rather simple ．
他上课总是迟到的原因很简单。

8．from where有时也被用来引导定语从句，此时的where应是关系代词。

如：His head soon appeared out of one of the second storey window ，from where he could see nothing but trees．
不一会儿，他从二楼的一扇窗户里探出头来，除了树林之外，从那里什么也看不到。

He climbed up the top of the temple ，from where he could see some things in the distance ．
他爬上了寺庙的顶部，从那里他可以看到远处的一些东西。

以上来自百度文库，不是个人总结。但是绝对有用，先学习了，希望也帮到你。。

“介词＋关系代词 +不定式短语 作后置定语，相当于一个定语从句 楼上 已讲 不再重复
补充 两点
一、“介词+关系代词+带to不定式”结构中的介词，不能是短语动词不定式中的介词。例如下面一句中的定语从句不能转换成这一结构。
The man who，in old age，can see his life in this way，will not suffer from the fear of death，since things he cares for will continue．
(不能转换成for which to care)
上了年纪而能这样看待生活的人，不会害怕死，因为他所关心的事情将会继续下去。
二：“介词+关系代词+带to不定式”结构中的不定式不能是被动形式。例如下面一句中的定语从句不能转换成这一结构。
The government agrees to install services which are to be paid for by residents over a ten-year period．

有这种情况
She had no time left in which to pack her things
他没有时间收拾行李了
先行词是time,关系代词是which
which代表time,但实际上后面不是定语从句
而是不定式
to pack her things in the time
in which to pack her things全部看成是修饰time的就可以了

After the harvest,the peasants selected their best produce with which
to pay their tax to the state.
收了庄稼，农民选最好的粮食来交税
which代表produce,农作物
to pay their tax to the state with produce
用农作物来当作税交国家
with which to pay their tax to the state.
整个就看成是定语来修饰produce
虽然是不定式