http://wenku.baidu.com/view/101fa43631126edb6f1a101e.html

定語從句中的whichthat
thatwhich從句里都可以做賓語和主語,做賓語時可以省略。(The place which\that\不填Ivisited yesterday was boring.)在定語從句中,關(guān)系代詞在限制性定語從句中作賓語可以省略,不管是thatwhich,還是whom。但是which能引導(dǎo)非限制性定語從句,that則不行
只能用that的幾種情況
1. 當(dāng)先行詞為all, much, little, none及由any, every, some, no所構(gòu)成的復(fù)合不定代詞時
如:We should do all that is useful to the people.  我們應(yīng)該做一切有益于人民的事情。 
Please tell me anything that you know about the matter. 有關(guān)此事,凡是你所知道的請告訴我。
2. 當(dāng)先行詞被any, few, little, no, all, much, some等詞修飾時。
如:You can take any seat that is free. 任何空著的座位你都可以坐。
There is little work that is fit for you. 幾乎沒有適合你的工作。
3. 當(dāng)先行詞為序數(shù)詞或被序數(shù)詞所修飾時。
如:When people talk about the cities of China, the first that comes to my mind is Beijing. 人們談?wù)撈鹬袊某鞘械臅r候,我首先想到的是北京。
This is the fourth film that has been shown in our school this term. 這是我們校本學(xué)期放映的第四部電影。
4. 當(dāng)先行詞為形容詞最高級或被形容詞最高級修飾時(the best , the most等)
如:The best that I could do was to apologize. 我唯一能做的就是賠禮道歉了。
This is the most interesting story book that I have ever read. 這是我讀過的一本最有趣的故事書。
5. 當(dāng)先行詞被the very, the only, the last, the just, the same等修飾時。
如: This is the very book that I’m looking for. 這正是我在找的書。
The only thing that we could do was to wait. 我們唯一能做的事就是等待。
注意:先行詞被the same修飾時,關(guān)系代詞也可用as。如:I need the same book that / as you have. 我需要有你一樣的書。
6. 當(dāng)先行詞既包含人又包含物時。
如: They are talking of the heroines and their deeds that interest them. 他們正在談?wù)撍麄兏信d趣的女英雄及她們的事跡。
7. 當(dāng)先行詞是疑問代詞whowhichwhat或主句以這些詞開頭時。
如:Who that has ever worked together with him doesn’t admire him? 曾經(jīng)和他一起工作過的誰不欽佩他?
Which is the star that is nearer to the earth 哪個是離地球比較近的星星?
8. 當(dāng)先行詞為主句表語或關(guān)系代詞為從句表語時。
如:That’s a good book that will help you a lot. 那是本對你很有幫助的書。
Our school is no longer the place that it used to be. 我們的學(xué)校現(xiàn)在已不是過去的那個樣子了。
9. 先行詞為time時,當(dāng)time表示次數(shù),引導(dǎo)詞用that, 可省略。 當(dāng)表示時間,可用thatwhen引導(dǎo),都可省略。
如:I do remember the first time(that) I had ever heard the sweetest voice in the world.我很清楚地記得當(dāng)我第一次聽到世界上最美的聲音的時候。
I did't remember the exact time when/that I arrived in Shanghai last month. 我不記得上個月到達(dá)上海的確切時間了。
10.在固定結(jié)構(gòu)the same...that...; so...that...; such...that...以及it is/was...that...的強(qiáng)調(diào)句型中,須用that如:
This is the same museum that you once visited.
 
只能使用which的情況:
1.     介詞+關(guān)系代詞結(jié)構(gòu)中,關(guān)系代詞必須用which如: 
The house in which we live is very large. 我們住的房子非常大。 This is the reference book of which the teacher is speaking. 這就是老師正在談及的那本參考書。 
注意: 如果介詞不放在修飾事物的限定性定語從句的句首, which就可換為that 如: 
This is the question which/that we’ve had so much discussion about. =This is the question about which we’ve had so much discussion. 這就是我們已經(jīng)多次討論過的問題。 
2. 先行詞為“those+表事物的復(fù)數(shù)名詞時, 關(guān)系代詞通常只用which而不用that如:
you should grasp well those skills which may be used in the future work.
3.如果先行詞是that,關(guān)系代詞應(yīng)用 which
I have that which you gave me.
4.一個句子中如有兩個定語從句,第一個定語從句用了關(guān)系代詞that,第二個從句中的關(guān)系代詞宜用which但在平行結(jié)構(gòu)中,應(yīng)重復(fù)同一個關(guān)系代詞如:
This is the book that you bought which you have lost. 
I have a house which is located on the hillside, which faces the south.
5.如先行詞和定語從句之間被其它較長的成分分隔,常用which?
Larry told her the story of the young airman which I narrated at the beginning of this book.  (先行詞為story)
 
特殊情況:當(dāng)先行詞是表示原因或方式的名詞時,可以用that引導(dǎo)定語從句,相當(dāng)于介詞+whichthat可以省略。
如: She likes the child for the very reason that (=for which) she loves his father. 她喜歡那個孩子因為她愛著孩子的父親。
He didn’t like the way that (=in which = \) she speaks to his mother. 他不喜歡她對他的母親那樣說話。
The reason (that /for which /why) he came here was to ask for our help.他來這里的原因是尋求我們的幫助。