一、定語從句:
1.定語從句的概念：在復合句中，修飾某一名詞或代詞的從句叫定語從句。
2.先行詞：被定語從句修飾的名詞或代詞叫先行詞。
3.關系詞：引導定語從句的連詞叫關系詞。如that、which、who、whom、whose、where、when等。
4.由that、which、who、whom、whose引導的定語從句。
關系詞 指代 在定語從句中的作用
that 既指人也指物 作主語、賓語
which 指物 作主語、賓語
who 指人 作主語
whom 指人 作賓語
whose 既指人也指物 作定語
二、定語從句：1.先行詞是物時，一般情況既可用that，which均可.但下列情況，只用that不用which。
1).當先行詞為指物的不定代詞，如all、everything、something、anything、nothing、none、the one等時，只能用that。There is nothing ______ I can do for you .
2).先行詞被the only,the very,the last,all,no,little等詞修飾,只用that。This is the very book ___ I’m looking for .
3).先行詞被序數詞修飾時，只用that . This is the first nextbook ______ I studied in the middle school .
4).先行詞為最高級或被最高級修飾時，只能用that。
This is the most beautiful mountain ______ I have ever seen .=I have _____ seen _____ a beautiful mountian .
5).先行詞既有人也有物時，只能that 。 He told us many interesting things and persons _______ we had .
2.先行詞是物時，一般情況既可用that也可用which.但下列情況，只能用which不用that。
1).關系代詞前有介詞時，關系詞只能用which 。This is the building in ______ he lives .
2).先行詞本身是that時，關系詞只能用which 。The clock is that _____ tells the time .
3).引導非限定性的定語從句（先行詞是物且先行詞與關系詞用逗號隔開），關系詞用which。
His book , ______ was lost last week , has been found now.
3.先行詞是人時，一般情況下既可用who 也可用that 。但以下情況下，只能用who。
1).當先行詞為those、one、ones、anyone且作主語時,一般用who .Those ____ are singing are all my classmates .
2).在there be 句型中，先行詞指人時，只能用who。指物時用that。There is a girl ______ expects to see you .
3).當先行詞是I、you、he、they等時，只能用who 。He ______ plays with fire gets burned .
三、定語從句 由關系副詞when、where、why引導的定語從句。
where = in / at +which when = in / on / at +which why = for + which
1.由where引導的定語從句。1).先行詞是表示地點的名詞 2).在定語從句中作地點狀語
Is this the house ____ you lived ?= Is this the house ____ ___ you lived ?= Is this the house ___ you lived in ?
2.由when引導的定語從句。1).先行詞是表示時間的名詞 2).在定語從句中作時間狀語
I will never forget the days ______ I met him .= I will never forget the days ____ ____ I met him.
注：先行詞是the last time 時，when 可省略。When was the last time you saw the parrot ?
3.由why引導的定語從句。先行詞為reason 時，一般用why 。 why在句中作原因狀語。
We don’t know the reason ______ they didn’t come .
四、注意事項：
1.關系詞在定語從句中作賓語時，常可省略。The story _____ he told was very popular .
A.who B.whom C.whose D. /
2.that、who、which在定語從句中作主語時，定語從句的謂語動詞應與先行詞保持一致。
I loves singers who _______(write) their own songs ./She is one of the girls who ______(study) hard .
3.定語從句中whose 的確定：無論先行詞是人或物，在定語從句中做定語用whose。
判斷：看定語從句的主語前有無限定詞（my、your、Jim’s等），若沒有，則用whose 。
The girl _____ parents work in Beijing is Kate .A. who B. whose C. which D. that