定语从句
定语从句起了形容词的作用，在句中修饰一个名词或代词。被修饰的词叫做先行词，引导定语从句的词叫关系词，他的作用一是放在先行词与定语从句中间起了连接作用，二是在从句中担当一个成分，并与先行词保持数的一致。
定语从句掌握要点分析：一：掌握定语从句关系代词和关系副词的选用，以备选择题；二：掌握定语从句的翻译，以备阅读及完形填空和填空题的理解；三：掌握简单的定语从句的汉译英，以备在作文中能写出简单的含定语从句的句子。
关系词 先行词 从句成分 例句 备注
关系代词 who 人 主语 Do you know the man who is talking with your mother? whom, which和that在从句中做宾语时，常可以省略，但介词提前时后面关系代词不能省略，也不可以用that
whom 人 宾语 Mr. Smith is the person with whom I am working
The boy (whom) she loved died in the war..
whose 人，物 定语 I like those books whose topics(the topics of which) are about history.
The boy whose father works abroad is my deskmate.
that 人，物 主语，宾语 A plane is a machine that can fly.
She is the pop star (that) I want to see very much.
which 物 主语，宾语 The book (which) I gave you was worth $10.
The picture which was about the accident was terrible.
as 人，物 主语，宾语 He is such a person as is respected by all of us.
This is the same pen as I lost yesterday. as做宾语一般不省略
关系副词 when 时间 时间状语 I will never forget the day when we met there. 可用on which
where 地点 地点状语 This is the house where I was born. 可用in which
why 原因 原因状语 I can’t imagine the reason why he turned down my offer. 可用for which
II. that与which, who, whom的用法区别：
情况 用法说明 例句
只用that的情况 先行词为all, everything, anything, nothing, little, much,等不定代词时。
先行词被all, any, every, each, much, little, no, some, few等修饰时
先行词有形容词最高级和序数词修饰时
先行词既指人又指物时
先行词被the only, the very修饰时
句中已经有who或which时，为了避免重复时 1.He told me everything that he knows.
2.All the books that you offered has been given out.
3.This is the best film that I have ever read.
4.We talked about the persons and things that we remembered.
5.He is the only man that I want to see.
6.Who is the man that is making a speech?
只用which, who, whom的情况 在非限制性定语从句中，只能用which指代物，用who/whom指人
在由“介词+关系代词”引导的定语从句中，只能用which指物，whom指人。
先行词本身是that时，关系词用which, 先行词为those, one, he时多用who。 He has a son, who has gone abroad for further study.
I like the person to whom the teacher is talking.
Those who respect others are usually respected by others.
一：定语从句关系代词和关系副词的选用：
掌握在一个句子中，定语从句出现在什么地方？--在名词或代词后。
掌握定语从句关系代词和关系副词的选用：
1）. 找出先行词（即被定语从句所修饰的词）
2）．将先行词放入后面的定语从句中，看作何成分，指人还是指物；
3）．关系代词（定语从句不完整时用）：Who(指人，作主语或宾语) whom (指人，作宾语) that which （指物，作主语或宾语，其中，that 不用于非限制性定语从句） whose (指人和物，作定语) ；
4）.关系副词（定语从句完整时用）：when (作时间状语)， where (作地点状语)， why(作原因状语)， how(作方式状语)；(见上表)
二.which、as 可表示“这一点”，指代前面句子的内容；其中当谓语动词为be 时或置于句首时只能用as；as 还有“正如”之意
三．Such … as；the same …as （定语从句“象(和)……样的”as 在定语从句中作成分）与 such … that； （结果状语从句“如此 … 以致, that 后句子完整）的区别
四．What 不用于定语从句。
五. 先行词和关系词二合一
1)Whoever spits in public will be punished here. (Whoever 可以用 anyone who 代替)
2)The parents will use what they have to send their son to technical school. (what 可以用all that代替)
六. what/whatever;that/what; who/whoever
1）what = the thing which；whatever = anything that
What you want has been sent here.
Whatever you want makes no difference to me.
2) who= the person that whoever= anyone who
（错）Who breaks the law will be punished.
（错）Whoever robbed the bank is not clear.
（对）Whoever breaks the law will be punished.
（对）Who robbed the bank is not clear.
七. that 和 what
当that引导定语从句时 ，通常用作关系代词，而引导名词性从句时，是个不充当任何成分的连接词。宾语从句和表语从句中的that常可省略。What只能引导名词性从句， 用作连接代词，作从句的具体成分，且不能省略。
I think (that) you will like the stamps.
What we need is more practice.