第1个回答 2012-08-07
I. 定义：定语是修饰名词或代词的成分,定语可由单词、短语来充当。当用一个句子来充当名词或代词的修饰语时，这种起定语作用的句子就被称为定语从句。
They have a clever son.
Do you know the man over there?
I know the man who wrote the book.
II. 要点：
1． 定语从句的前面都有先行词（被修饰语）
This is the boy whom we are looking for
2． 定语从句应紧跟在先行词之后
3． 先行词与定语从句之间要有关系词（有时可省略）
4． 关系词在定语从句中充当某一成分
The girl who is standing under the tree is my sister.
The man whom you want to see has come.
III. 关系词基本用法
主格
宾格
所有格
人
who
whom
whose
物
which
which
of which
但that 一般可用来代替who, whom, which,作宾格时可省略
Do you remember the teacher that/who taught us English?
A bookstore is a store that/which sells books.
The man (that/whom/who) you know is a famous professor.
A) that 不能用来替代who, whom, which的两种情况
1）“介词+whom/which”的结构中，不能用that
She is a good student from whom we should learn.
2) 在非限制性定语从句中，逗号后面不能用that
She sang a new song, which we like very much.
注意：非限制性定语从句的关系代词不能省略
B) 用that不用which的一些特殊情况
1) 先行词为all, much, little, something, anything, everything, nothing等
Is there anything (that) I can do for you?
2) 先行词前有形容词最高级修饰
This is the most exciting report that I have ever read.
3) 先行词前有first, last, next, only, very, all, any等词修饰
The first step (that) we are to take is very difficult.
4) 先行词同时含有“人”和“非人”时，用that 不用which，也不用who/whom
He talked about the people and the books that interested him.
C) 关系副词when, where, why
用关系副词when时，它的先行词是表示时间的名词，用where时先行词是表示地点的名词，而用why时它的先行词只可能是reason，使用时应注意以下几点：
1） 关系代词的选择主要是看先行词在从句中所作的成分
This is the city where I was born.
This is the city (which/that) he has visited
I don’t know the reason why she is late.
That is the reason (which/that) everybody knows
Do you still remember the day when he arrived?
Do you still remember the day (that/which) we spent together?
2） 关系副词when,where, why可由“介词+which”的结构来替代
Is this the reason for which they came?
He left the day on which I came.
注意：how 不能用来引导定语从句
This is the way how he did it.
D) As 作关系代词的用法
与the same, such连用
This is the same book as I read last week.
Such books as I have read are classical works.