关系代词有：who, whom, whose, that, which等。
关系副词有：when, where, why等。
1)who, whom, that
Is he the man who/that wants to see you?
He is the man whom/ that I saw yesterday.
2) Whose 用来指人或物，(只用作定语, 若指物，它还可以同of which互换), 例如： They rushed over to help the man whose car had broken down.
Please pass me the book whose (of which) cover is green.
它们所代替的先行词是事物的名词或代词，在从句中可作主语、宾语等， 例如：A prosperity which / that had never been seen before appears in the countryside.
农村出现了前所未有的繁荣。(which / that在句中作宾语)
The package (which / that) you are carrying is about to come unwrapped. 你拿的包快散了。(which / that在句中作宾语)
1)when, where, why
关系副词when, where, why的含义相当于"介词+ which"结构，因此常常和"介词+ which"结构交替使用，例如：
There are occasions when (on which) one must yield.
Beijing is the place where (in which) I was born. 北京是我的出生地。 Is this the reason why (for which) he refused our offer?
方法一： 用关系代词，还是关系副词完全取决于从句中的谓语动词。及物动词后面无宾语，就必须要求用关系代词;而不及物动词则要求用关系副词。例如： 1
This is the mountain village where I stayed last year.
I'll never forget the days when I worked together with you.
判断改错(注：先显示题，再显示答案，横线;用不同的颜色表示出。) (错) This is the mountain village where I visited last year.
(错) I will never forget the days when I spent in the countryside.
(对) This is the mountain village (which) I visited last year.
(对) I'll never forget the days (which) I spent in the countryside.
习惯上总把表地点或时间的名词与关系副词 where, when联系在一起。此两题错在关系词的误用上。
例1. Is this museum ___ you visited a few days age?
A. where B. that C. on which D. the one
例2. Is this the museum ____ the exhibition was held.
A. where B. that C. on which D. the one
答案：例1 D，例2 A
例1变为肯定句： This museum is ___ you visited a few days ago.
例2变为肯定句： This is the museum ___ the exhibition was held.
在句1中，所缺部分为宾语，而where, that, on which都不能起到宾语的作用，只有the one既做了主句的表语，又可做从句的宾语，可以省略关系代词，所以应选D。
而句2中, 主、谓、宾俱全，从句部分为句子的状语表地点，既可用副词where，又因 in the museum词组，可用介词in + which 引导地点状语。而此题中，介词on 用的不对，所以选A。
关系词的选择依据在从句中所做的成分，先行词在从句中做主、定、宾语时，选择关系代词 (who, whom, that, which, whose); 先行词在从句中做状语时，应选择关系副词 ( where 地点状语，when 时间状语，why 原因状语) 。
1) 定语从句有限制性和非限制性两种。限制性定语从句是先行词不可缺少的部分，去掉它主句意思往往不明确;非限制性定语从句是先行词的附加说明，去掉了也不会影响主句的意思，它与主句之间通常用逗号分开，例如： This is the house which we bought last month.
The house, which we bought last month, is very nice.
Charles Smith, who was my former teacher, retired last year.
My house, which I bought last year, has got a lovely garden.
This novel, which I have read three times, is very touching.
3) 非限制性定语从句还能将整个主句作为先行词, 对其进行修饰, 这时从句谓语动词要用第三人称单数，例如：
He seems not to have grasped what I meant, which greatly upsets me.
Liquid water changes to vapor, which is called evaporation.
说明：关系代词that和关系副词why不能引导非限制性定语从句。 5. which 与 that 的区别
He changed his mind, which made me very angry.
The car that we came in ran over a dog．
This is the kind of life that he is used to．
The train ran over a boy and a dog that were crossing the track．
I like the writers and books that you remind me the other day．
He talked about the teachers and schools that he had visited．
This is the best novel that I have ever read．
Beijing is the most beautiful city that has many places of interest．
It was the finest industrial exhibition that we ever saw．
She is the same teacher that was praised the other day．
She wore the same dress that she wore at Mary's wedding．
He is doing the same job that he did last year．
但下面两句要注意辨析：①This is the same watch that I lost the other day． （that关系代词表示同一块手表即原手表）
②This is the same watch as I lost the other day．
4）当定语从句的先行词是all，everything，nothing，anything，little，much，few，none或由any，no，every，same将构成的合成词时，我们通常用that。 Everything that can be done must be done．
Is there anything that I can do for you？
He talked much that was important．
5）当先行词被the only，the very，the last，the most，the any，the next等修
This is the very book that you are interested in。
Mary is the only woman that we can safely depend on．
That is the last place that I want to visit．
Jack was the first one that reached the top of the mountain that day．
The first thing that we should do is to work out a plan．
He is the third student who came to school this morning．
There is somebody that wants to see you．
I was the only person in my office that was invited．
A new master wi1l come tomorrow that will teach you German．
Which of us that is always 38 years old has been to Beijing？
Who is the person that is standing at the gate？
Who that has common sense will do such a thing？
China is not the country (that) it was. 中国已不是过去的样子了
1. The place _______interested me most was the Children's Palace.
A. Which B. where C. what D. in which
2. Do you know the man _______?
A. whom I spoke B. to who spoke
C. I spoke to D. that I spoke
3. This is the hotel _______last month.
A. which they stayed B. at that they stayed
C. where they stayed at D. where they stayed
4. Do you know the year ______the Chinese Communist Party was founded?
A. which B. that C. when D. on which
5. That is the day ______I'll never forget.
A. which B. on which C. in which D. when
6. The factory ______we'll visit next week is not far from here.
A. where B. to which C. which D. in which
7. Great changes have taken place since then in the factory _______we are working.
A. where B. that C. which D. there
8. This is one of the best films _______.
A. that have been shown this year
B. that have shown
C. that has been shown this year
D. that you talked
9. Can you lend me the book ___the other day?
A. about which you talked
B. which you talked
C. about that you talked
D. that you talked
10.The pen ______he is writing is mine.
A. with which B. in which
C. on which D. by which
11.They arrived at a farmhouse, in front of ______sat a small boy.
A. whom B. who C. which D. that
12.The engineer ______my father works is about 50 years old.
A. to whom B. on whom
C. with which D. with whom
13.It there anyone in your class ______family is in the country?
A. who B. who's C. which D. whose
14.I'm interested in ______you have said.
A. all that B. all what C. that D. which
15.I want to use the same dictionary ______was used yesterday.
A. which B. who C. what D. as