一、定语从句:
1.定语从句的概念：在复合句中，修饰某一名词或代词的从句叫定语从句。
2.先行词：被定语从句修饰的名词或代词叫先行词。
3.关系词：引导定语从句的连词叫关系词。如that、which、who、whom、whose、where、when等。
4.由that、which、who、whom、whose引导的定语从句。
关系词 指代 在定语从句中的作用
that 既指人也指物 作主语、宾语
which 指物 作主语、宾语
who 指人 作主语
whom 指人 作宾语
whose 既指人也指物 作定语
二、定语从句：1.先行词是物时，一般情况既可用that，which均可.但下列情况，只用that不用which。
1).当先行词为指物的不定代词，如all、everything、something、anything、nothing、none、the one等时，只能用that。There is nothing ______ I can do for you .
2).先行词被the only,the very,the last,all,no,little等词修饰,只用that。This is the very book ___ I’m looking for .
3).先行词被序数词修饰时，只用that . This is the first nextbook ______ I studied in the middle school .
4).先行词为最高级或被最高级修饰时，只能用that。
This is the most beautiful mountain ______ I have ever seen .=I have _____ seen _____ a beautiful mountian .
5).先行词既有人也有物时，只能that 。 He told us many interesting things and persons _______ we had .
2.先行词是物时，一般情况既可用that也可用which.但下列情况，只能用which不用that。
1).关系代词前有介词时，关系词只能用which 。This is the building in ______ he lives .
2).先行词本身是that时，关系词只能用which 。The clock is that _____ tells the time .
3).引导非限定性的定语从句（先行词是物且先行词与关系词用逗号隔开），关系词用which。
His book , ______ was lost last week , has been found now.
3.先行词是人时，一般情况下既可用who 也可用that 。但以下情况下，只能用who。
1).当先行词为those、one、ones、anyone且作主语时,一般用who .Those ____ are singing are all my classmates .
2).在there be 句型中，先行词指人时，只能用who。指物时用that。There is a girl ______ expects to see you .
3).当先行词是I、you、he、they等时，只能用who 。He ______ plays with fire gets burned .
三、定语从句 由关系副词when、where、why引导的定语从句。
where = in / at +which when = in / on / at +which why = for + which
1.由where引导的定语从句。1).先行词是表示地点的名词 2).在定语从句中作地点状语
Is this the house ____ you lived ?= Is this the house ____ ___ you lived ?= Is this the house ___ you lived in ?
2.由when引导的定语从句。1).先行词是表示时间的名词 2).在定语从句中作时间状语
I will never forget the days ______ I met him .= I will never forget the days ____ ____ I met him.
注：先行词是the last time 时，when 可省略。When was the last time you saw the parrot ?
3.由why引导的定语从句。先行词为reason 时，一般用why 。 why在句中作原因状语。
We don’t know the reason ______ they didn’t come .
四、注意事项：
1.关系词在定语从句中作宾语时，常可省略。The story _____ he told was very popular .
A.who B.whom C.whose D. /
2.that、who、which在定语从句中作主语时，定语从句的谓语动词应与先行词保持一致。
I loves singers who _______(write) their own songs ./She is one of the girls who ______(study) hard .
3.定语从句中whose 的确定：无论先行词是人或物，在定语从句中做定语用whose。
判断：看定语从句的主语前有无限定词（my、your、Jim’s等），若没有，则用whose 。
The girl _____ parents work in Beijing is Kate .A. who B. whose C. which D. that