定语从句语法总结
介词的选用可根据从句中的相关词组确定，该介词通常可以放在关系代词之前，也可放在从句之尾。以下是小编为大家整理分享的定语从句语法总结，欢迎阅读参考。
定语从句语法总结
一．几个基本概念1、定语从句的定义：用作定语的从句叫定语从句。
2、先行词：被定语从句所修饰的名词或代词。
3、定语从句的位置：紧跟先行词（名词或代词）之后。
4、引导词：引导定语从句的词（包括关系代词和关系副词）。
（1）关系代词：that/who/whom/which/as
（2）关系副词：when/where/why
5、引导词的位置：位于定语从句之前（先行词之后）。【as除外】
6、引导词的功能（作用）：
（1）连接先行词和定语从句。
（2）在定语从句中充当一定的成分（关系代词充当主语或宾语，关系副词充当状语）。
7、定语从句的类型：
（1）限定性定语从句（主句和定语从句之间无逗号）。
① 直接由引导词引导定语从句
The man who you’re talking to is my friend、
② 由介词+关系代词（whom/which）引导
The man to whom you’re talking is my friend、
I need a pen with which I can write a letter、
=I need a piece of paper on which I can write a letter、
介词的选用可根据从句中的相关词组确定，该介词通常可以放在关系代词之前，也可放在从句之尾。例如：
The man (who/whom/that) I talked about at the meeting is from Beijing University、
=The man about whom I talked at the meeting is from Beijing University、
The palace (which/that) I often pay a visit to was built in the 17th century、
=The palace to which I often pay a visit was built in the 17th century、
（2）非限定性定语从句（主句和定语从句之间用逗号隔开）。
① 直接由引导词引导定语从句。
② 由介词+关系代词（whom/which）引导。
I live in a house far away from the city, in front of which is a big tree、
There is an apple tree standing at the gate, on which are many apples、
This is the man to whom I gave the book、
③ 由“代词/名词+of+whom/which”或“of which/ whom +名词/代词”(先行词指
人用whom,指物用which)引导。One, some, any, none, all, both, several, many, most, neither, either等词、数词、分数或百分比与of whom或of which连用。
He has five children, two of whom are abroad、
(比较：He has five children, and two of them are abroad、)
We have three books, none of which is/are interesting、
(比较：We have three books, but none of them is/are interesting、)
除why和that不能引导非限定性定语从句外，其余引导词都可以，用法同限定性定语从句一样。但要注意以下区别。
1、在形式上非限定性定语从句与主句有逗号隔开。
2、非限定性定语从句的作用：它只是补充说明先行词的情况，翻译时可译成两个句子。
The engineer, whose leg was badly hurt, was quickly sent to hospital、
（那位工程师被很快送往医院，其腿部受了重伤）
The engineer whose leg was badly hurt was quickly sent to hospital、
（那位腿部受了重伤的工程师被很快送往医院）
3、在非限定性定语从句中，任何引导词都不能省略（包括引导词在此定语从句中充当宾语在内）。指人做主语时只能用who, 做宾语时用whom; [要学习网-中学生最喜欢的学习论坛；网址、yaoxuexi、cn手机版地址wap、yaoxuexi、cn]
指物做主语，宾语都用which; 关系副词用when或where，也不能省略。
The man, ______ is sitting on the chair, is my father、
The woman, _______ I met yesterday, is my English teacher、
The city, _______ is far away, is very beautiful、
He went to America, ______ his parents live、
He joined the Army yesterday, ______ I left, too、
4、whose引导非限定性定语从句：
The house, whose window faces south, is mine、
=The house, the window of which faces south, is mine、
＝The house, of which the window faces south, is mine、
二、定语从句中关系代词和关系副词的基本用法
1、who/that指人是主格在定语从句中代替先行词，又作定语从句的'主语，不能省略。
Do you know the gentleman who/that is sitting there?
2、whom/who/that指人是宾格，在定语从句中代替先行词，又作定语从句的宾语（动宾或介宾）。
① 当作动宾（动词后接宾语）时，关系代词可省略。
Do you know the gentleman (whom/who/that) we met just now?
② 当作介宾（介词后接宾语）时：
介词不提前时，关系代词可省略；
介词提前时，关系代词不可省，即介词＋whom(指人时介词后的关系代词只能用whom)。
The man (whom/who/that) I spoke with is my teacher、
The man with whom I spoke is my teacher、
※注：固定的动词短语（动词+介词）如look for, take care of等不能把动词与介词拆开，既介词不能提至引导词前。
She is the right girl (who/whom/that) we are looking for、
3、whose: 指人或物，是所有格“…的”形式。Whose+n、一起在定语从句中充当主语、宾语（动宾或介宾）即先行词的什么东西怎样了，whose不能省略。。Whose+n、 = the +n、 + of which/whom= of which/ whom+ the =n、
I didn’t find the desk whose leg was broken、 （主语）
He is the student whose pencil I broke yesterday、 （动宾）
The boss in whose pany I work is very kind、 （介宾）
4、which/that 指物，指代先行词且在定语从句中作主语或宾语（动宾或介宾）。
① 当作动宾时，关系代词可省略。
② 当作介宾时：
介词不提前时，关系代词可省略；
介词提前时，关系代词不可省，即介词＋which(指物时介词后的关系代词只能用which)。
The house which/that was destroyed in the earthquake is weak、
The pen (which/that) you found yesterday is mine、
The games (that/which) the young men peted in were difficult、
The games in which the young men peted were difficult、
※注:介词+关系代词即介词+whom/which(先行词指人用whom，指物用which)。
※5、as指人或物，在定语从句中可作主语，宾语，表语或状语，不能省略。主要用于 “the same …as…；such …as…；so …as…；as … as…；as follows”固定结构中，形式固定此时的引导限定性定语从句。要用as代替who(m), which, 或that引导定语从句：
Such people as knew Hill thought he was honest、
Such people as Hill knew thought he was honest、
My hometown is no longer the same as it was、
Here is so big a stone as no one can lift、
The child knows as much as grow-ups (know)、
I’d like to have the same books as are used in your school、
He is not such a person as I expected、
He will marry as pretty a girl as he can find、
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