定语从句的结构

从句结构
先行词
指被定语从句修饰的名词、代词。
一般先行词出现在定语从句的前面。　[1]
关联词
关联词常有2个作用：
①连接作用，引导定语从句。
②代替先行词，在定语从句中担当一个成分。
注：关系代词有主语、宾语、定语之分。一般who做主语或其宾格形式的whom做宾语，whose作为定语（whom，whose不可省略）。关系代词在从句中作主语，宾语，定语等，关系副词在从句中作地点状语（where）时间状语（when），原因状语（why）。[1]
定语
定语用来限定、修饰名词或代词，是对名词或代词起修饰、限定作用的词、短语（动词不定式短语、动名词表示的）汉语中常用“……的”表示。主要由形容词担任，此外，名词、代词、数词、分词、副词、不定式以及介词短语也可以来担任，也可以由一个句子来担任。单词作定语时通常放在它所修饰的词之前，作前置定语。短语、从句作定语时则放在所修饰的词之后，作后置定语。
被定语从句修饰的名词、代词称为先行词。如“the
girl”，“the
book”
如:She
is
the
girl
who
likes
singing.
她就是那个爱唱歌的女孩。
这就是一个定语从句。[1]
http://baike.baidu.com/view/56536.htm#2

定语从句在复合句中修饰名词或代词（先行词），因此主要结构为：
先行词+关系词+定语从句
(关系词在定语从句中指代上文的先行词，在从句中根据所充当的不同句子充分而有所选择:who,
whom,
whose,
that,
whcih,
as,
when,
where,
why)

http://www.wwenglish.com/en/z/grammar/
这个网站的语法讲的很详细的,这个连接是关于定语从句的,有关其他从句也都有的,都看一遍就清楚了

http://baike.baidu.com/view/56536.html?wtp=tt
慢慢看

概述
1.定义：一个句子做定语叫做定语从句。
She is our new teacher who has just come back from the United States. 她是我们的新老师，刚从美国回来。
2.先行词：被修饰的部分叫先行词。先行词可以是一个词，也可以是一个句子。定语从句一般要在先行词之后。
a. This is the baby whom you will look after.
这就是你要照料的婴儿。
b. They have invited me to visit their country, which is very kind of them. 他们十分友好，邀请我访问他们的国家。
关系词
1.关系代词：that, which, who, whom, as, 在从句中作主语，宾语或表语；作宾语时一般可省略；whose在从句中作定语。
a. That was all that I wanted to tell you about .
那是我想要告诉你的一切。（宾语）
b. A scientist is a person who does scientific research.
科学家是搞科学研究的人。（主语）
c. The house whose door is brown is mine.
棕色的门的房子是我的。（宾语）
2.关系副词：where, when, why 在从句中作状语。
a. This is the school where I studied twenty years ago.
这是我二十年前学习过的学校。
b. I thought of my childhood when I lived in the village.
我想起了在村里度过的童年。
c. That's the reason why I'm not in favour of your plan.
那就是我不赞成你的计划的原因。
种类：
1.限定性定语从句：与主句关系密切，不可拿掉，否则整个句子的意思不完整。
The small town where I was born has developed into a big industrial city.
我出生的小城镇已经发展成为一个大的工业城市。
2.非限定性定语从句：对所修饰的部分作进一步说明，拿掉之后其他部分仍然成立。
I was born in a small town, which has developed into a big industrial city.
我出生在一个小城镇，它已经发展成了一个大的工业城市。
只用that引导的定语从句
在定语从句中，which 和that都可用来指物。一般可以互换，但下列情况只能用that 引导。1.先行词前有 the only, any, few, little, one of , no, every, the very 等词修饰时。
a. This is the only reason that I can give you.
这是我能给你的唯一理由。
b. There is no difficulty that can stop us from moving on .
没什么困难能阻止我们能继续前进。
2.先行词是不定代词all, everything, anything, nothing, the one, none, few, little, much 等词时。
c. Is there anything that I can do for you?
有什么我可以为你效劳的事吗？
d. This is all that I want to say.
这是我想说的一切。
3.以 which, who, what开头的问句时。
e. Which is the pen that you father gave you ?
哪一只是你父亲给你的钢笔？
f. Who is the girl that is reading there?
在那儿读书的女孩是谁？
g. What have you learnt that makes you so happy?
你听说什么了，使你这么高兴？
4.被修饰成分作表语或关系词本身作表语时。
h. She is not the little girl that she was ten years ago.
她不是十年前的小姑娘了。
i. China is no longer the country that it used to be.
中国不再是以前的老样子了。
5.先行词被形容词最高级修饰时。
j. This is the best film that I have ever seen.
这是我看过的最好的电影。
k. This is the most beautiful place that we have visited.
这是我访问过的最美的地方。
6.先行词被序数词修饰时。
l. I'll never forget the first day that we spent together.
我永远也忘不了我们在一起的第一天。
m. The last time that I met her was in 1976.
我最后一次见到她是1976年。
7.先行词为基数词时。
n. I've bought five books. You can still see the three that are on the desk.
我买了五本书。你仍可看到写字台上的三本。
8.先行词既有人又有物时。
o. They're talking about the people and the things that they saw.
他们谈论着所见到的人和事。
只用which 引导的定语从句
which 和that有时不可互换。以下情况只可用which。
1.引导非限制性定语从句。
a. He has a good knowledge of electricity, which helps him a lot in his work.
他在电学方面有良好的知识，这一点对他的工作帮助很大。
b. She was very patient towards the children, which her husband seldom was.
她对孩子非常耐心，她丈夫很少这样。
2.使用“介词+关系代词”这一结构时。
c. This is the room in which I lived twenty years ago.
这是我二十年前居住过的房间。
d. This is the question about which we've had so much discussion.
这是我们以讨论了多次的问题。
关系代词“ as ”的用法
as 引起定语从句时，可以放在主语前面；不可省略；多和 such, same连用。
a. As could be expected, he was against the plan.
正如预料的那样，他反对这个计划。
b. Such people as you describe are rare nowadays.
你所描述的人现在已很少见了。
c. I've the same trouble as you have.
我和你有同样的麻烦。
该用关系副词还是关系代词
先行词是表示时间或地点的名词时，并不都是用关系副词引导，而是要看关系词在从句中所作的成份。作状语时，用关系副词；作宾语时，仍然要用关系代词。
a. She is going to spend the summer holidays in Qingdao, where she has some relatives.
她打算去青岛过暑假，在那儿她有一些亲戚。（作状语）
b. This is the place which I visited last year.
这是我去年参观过的地方。（作宾语）
c. Did you still remember the days that we spent together in Hainan?
你还记得我们在海南一起度过的日子吗？（作宾语）
d. October 1st is the day which we Chinese people will never forget.
十月一日是我们中国人民永远不会忘记的日子。（作宾语）
关系代词的省略
1.在限定性宾语从句中作宾语或表语时一般都可省略：
a. Here is the man (whom) you've been looking for.
你一直在找的人在这儿。
b. He is no longer the man (that) he was.
他不再是以前的他了。
2.使用“介词+关系代词”结构时，不可省略：
a. This is the hospital in which I was born.
我是在这所医院出生的。
b. The old man with whom you talked yesterday is my grandfather.
昨天和你交谈的那老人是我爷爷。
3.非限定性定语从句中，宾语和表语也不可省略：
a. Tom, as everyone knows, is a bright boy.
大家都知道，汤姆是个聪明的男孩。
b. When deeply absorbed in work, which he often was, he would forget all about eating and sleeping..
他常常聚精会神做工作，这时他会废寝忘食。

定语从句在句中做定语，修饰句中的某一名词（或代词）。

被定语从句所修饰的词叫做先行词。

定语从句必须放在先行词之后。

引导定语从句的关联词有关系代词that（指人或物）、which（指物）、who（指人）。例如：

This is the building（that we built last year）．这就是我们去年建的楼房。

（that引导的定语从句修饰先行词building）

The man（who is talking with a group of students）is our headteacher．

正在和一群学生谈话的那个人是我们班主任。（who引导的定语从句修饰先行词man）

当关系代词在定语从句中做宾语时，关系代词常被省略去。例如：

The letter which I received yesterday was from a friend of mine．（＝The letter I received yesterday was from a friend of mine．）我昨天收到的那封信是我的朋友寄来的。

注：that引导的定语从句，所修饰的先行词既可指人也可指物；which引导的定语从句所修饰的先行词一般是物。这样that和which引导的定语从句都能修饰先行词“物”，它们有什么区别？分析如下：

A．在限定性定语从句中用that的情况：

1．当先行词前有一个最高级形容词所修饰的时候。例如：

This is one of the most exciting football games that I have ever seen．这是我所看过的足球赛中最激烈的一场。

2．当先行词前有一个序数词所修饰时。例如：

The first thing that you could do was to turn off the light．你首先要做的就是熄灭灯。

3．先行词为all，everything，nothing，something，anything，little，much，none等不定代词时。例如：

All that we have to do for our students is to tell them how to speak English in class．我们为学生所做的事情就是告诉他们如何在课上说英语。

I'm going to buy everything（that）I need．我要去买我所需要的一切东西。

4．当先行词前面有only，all，any，no等词修饰时。例如：

The only thing that he could do was to run away．他唯一要做的就是逃跑。

There are no people that things must not happen to．不碰到事故的人是没有的。

5．先行词为人、物共存时。例如：

We haven't met the man and his dog（that）were in the street yesterday．我们没有遇到昨天在大街上的那个人和他的狗。

B.在定语从句中用which的情况。

1．关系代词在介词后面时。例如：

This is the house in which Tom once lived．这是汤姆以前住过的房子。

2．先行词为that时。例如：

What's that which you are holding in your hands？你手里举的是什么？

3．在非限定性定语从句中。例如：

Football，which is a very in teresting game，is played all over the world．世界都踢足球，这是一项有趣的活动。

All the books here，which have beautiful pictures in them，were written by him．

这里所有的书都是由他写的，书中有漂亮的插图。