A Revision About Attributive Clause
I 定語從句的定義
在複合句中，修飾名詞或者代詞的從句叫定語從句。定語從句所修飾的詞叫做先行詞。如在課本中，（a）The man who lives next to us sells vegetable. (b) You must do everything that I can do. 斜體部分是先行詞。黑體部分是定語從句。第一句中定語從句修飾的是“the man ”這個名詞，而在第二句當中修飾的是“everything”這個代詞。其中，“who”和“that”叫做關係代詞。應到定語從句的詞有關係代詞that, which, who, whom, whose 和關係副詞where, when, why. 同時“as”也經常充當關係代詞，引導定語從句。
II 關係代詞that, which, who(whom)引導的定語從句(基本例句見課本)
1，其中that, who(whom)，都可以指人，那麼他們在指人時有什麼區別呢。[本條記憶技巧：用who 不用 that 的情況 “there be” “one，ones，anyone，nobody, those ” 被分割。***那裏有(there)很多萬(one)被那些人(those)分割。]
<1>先行詞為those, one, anyone, nobody 等詞時，用who不用that,例如：The one who knows me well is Tom.
<2>在分隔型定語從句中，若先行詞是人，用 who不用that, 例：
A new teacher will come who will teach you German.
在本句中，先行詞“teacher”和修飾限定它的從句 “who will teach you German ” 分離，所以我們用 who 不用 that。
<3>先行詞為“there be”結構的主語時，例如
There is a man who wants to see you.
在本句子當中a man是There is a man 這句當中的主語，所以用who不用that
2其中，that 和 which 都可以指物，它們在指物時的區別：
(1) 用that不用which
<1>先行詞前有形容詞最高級,序數詞,all, every, little, no, any, much, the only, the very, the last 等修飾時，例如：
I have read all the books that you gave me.
<2>先行詞為all, few, nothing, everything, little, much 等不定代詞時：
He did all that he could do to help us.
<3>主語以who或which開頭時
Who is the man that just called you just now?
<4>關係代詞在從句中做表語時
China is not the country that is was.
<5>既指人又指物時
He talked about the teachers and schools that he had visited.
2, 先行詞表示物時, 用which不用that 的情況
<1> 引導非限制性定語從句時,例如:
She heard a terrible noise, which brought her heart to her mouth.
<2>當關系代詞做介詞賓語時,例如:
He wrote a book in which he could learn about his life.
在上一例句中,引導詞 “which”作了介詞 “in”的賓語,所以不可以用 “that”代替.
III由whose， when， where why 等引導的定語從句可參考課本內容。這裏簡單介紹一下非限制性定語從句和限制性定語從句。非限制性定語從句，從意義上來説，是對主語的補充説明，從結構上來看，先行詞和定語從句之間用逗號隔開，He makes great progress in his English learning which makes his mother very happy.
IV 關於as
(1) 在一些結構，如“such …as” “the same…as” “as…as”等結構中，定語從句的引導詞經常要用到as，例如
This is not such a book as I expected.
(2) the same as和the same that 的區別。例句：
This is the same tool as I used last time.
This is the same tool that I used last time.
在例句中，第一句的意思是這個工具和我上次用的一樣，但是第二句的意思是這就是我上次用的工具
(3) as 和which 的比較
相同點：兩者都可以引導非限制性定語從句，先行詞都可以是整個句子，都可以在從句中做主語，賓語表語。
不同點<1>as 引導的從句可以放在句首和句尾，而which 引導的從句只可放在句尾。
<2>另外which 還有正如、正象的意思。
As Marx pointed out, labor created man himself.
當先行詞，雖然表示時間地點，但是引導詞在從句中不是做狀語時，而是做賓語時，不能用when, where引導，而只能用that, which 等引導。比較以下兩個句字：
I will never forget the days when I first went to Beijing .
I will never forget the days that (which) we spent together.
