定语从句
考纲要求：
掌握定语从句的基本知识；区分定语从句和名词性从句的性质和用法。
在具体的语境中考查非限制性定语从句的引导词以及“介词+关系代词”引导的定语从句；设置语境，考查抽象地点或时间概念的名词作先行词时关系副词的选择，甚至通过增加先行词的隐蔽性来增加试题的难度；考查定语从句的特殊句型，即：特定词汇+of whom/which 引导的定语从句。
复合句中修饰名词和代词的从句叫做定语从句，被修饰的名词或代词叫先行词。引导定语从的连接词有关系代词who, whom, that, which, whose, as 和关系副词when, why, where等。这些关系代词或关系副词有替代先行词，连接主句和从句，并在从句中充当成分三个作用。定语从句有限制性定语从句和非限制性定语从句两类。
限制性从句是句子不可缺少的部分，主句和从句间不用逗号隔开。
非限定性定语从句是对主句先行词的补充说明，去掉不影响主句意思的完整性。一般用逗号把主从句分开。关系代词that不可以引导非限定性定语从句，其他可引导定语从句的连词均可引导非限定性定语从句。
先行词：被定语从句修饰的名词或代词叫做先行词，定语从句必须放在先行词之后。有时先行词是关系代词前的整个句子。
1.当先行词是人：
关系词要用who, whom, that, whose等，其中who/that 在从句中课充当主语或宾语，whom 在从句中只能充当宾语，whose在从句中充当定语,不可省略(of whom 可以代替whose指人，词序是名词+of whom。)
This is the man who/that can speak several foreign language.（who/that 在从句中作主语，不可省略）
I like the girl (who/whom/that)you referred to yesterday.(who/whom/that 在从句中作宾语，可省略）
The government tried to help the old woman whose son (of whom the son/the son of whom）died in the war. [注意：whose与所修饰名词之间无任何冠词，否则要用of whom]
注意：
➢若连接词在从句中作介词宾语并且介词在前面，代替人必须用whom，且不可省略There is nobody in the street to whom I can turn for help.(turn to sb for help 求助于某人)
➢若介词在后面，则who, whom或that均可引导从句，且可以省略。
There is nobody in the street that /who/whom I can turn to for help.
（填一填）The settlement is home to nearly 1000 people, many of ________ left their village homes for a better life in the city.
➢在下列情况下多用who或whom,而不用that
①先行词是all, anyone, one, ones, those, people等时
All who can dance well will be invited.（who在从句中作主语）
Those who (whom)he knows will be invited.(who/whom在从句中作宾语）
②在被分割的定语从句中
A new teacher will come who will teach us English.
③在there be句型中
There is a girl who wants to see you.
④一个句子中有两个定语从句，其中一个用that引导，为了避免重复，另一个用who.
Every student that is from China who likes English will have a chance to get a book.
2.当先行词是物：
连接词要用which，that，whose，which/that在从句中作主语或宾语；whose在从句中作定语，后直接跟名词，无冠词，若有则用of which。（whose是一个表示所属关系的词,在定语从句中做定语,相当于my, his, her, its, their 等修饰人或物。of which可以代替whose指物，词序一般是名词+of which或of which+名词。）
The building which/that stands in the center is our school library.（which/that在从句中作主语，不可省略）
This is the book (which/that)you want.(which/that 在句中作宾语，可以省略）
The building whose window (of which the window)faces south is our school library.(作定语）（填一填）Look out! Don't get close to the house ________ roof is under repair.
注意：
➢如果关系代词在句中作介词宾语并且介词在前面，必须用which，且不可省略。
The house in which I live is near yours.
The house (that/which )I live in is near yours.
