3. 代表物时多用which，但在带有下列词的句子中用that而不用which，这些词包括all, anything, much等，这时的that常被省略
By the time you arrive in London, we will have stayed there for two weeks.
I still remember the first time I met her.
Each time he goes to business trip, he brings a lot of living necessities, such as towers, soap, toothbrush etc.
8. 当从句的逻辑主语是some, any, no, somebody, anybody, nobody, something, anything, everything或nothing时，常用there is来引导
2. 在引导限定性定语从句时，that有时相当于in which, at which, for which或at which
Attitudes towards daydreaming are changing in much the same way that(in which) attitudes towards night dreaming have changed. 人们对白日做梦的态度正在改变，这与人们对夜间做梦的看法的变化有非常相似之处。
I like the music for the very reason that(for which) he dislike it. 我出于某种原因喜欢这种音乐，而他恰恰与我相反。
We arrived the day that(on which) they left. 刚好我们到的那天他们走了。
4. 在非限定性定语从句中，不能用that，而用who, whom代表人，用which代表事物.
关系词有关系代词和关系副词。关系代词有that, which, who, whom, whose, as等；关系副词有where, when, why等。
(1) The boys who are playing football are from Class One.
(2) Yesterday I helped an old man who lost his way.
(1) Mr. Liu is the person (whom) you talked about on the bus.
(2) Mr. Ling is just the boy whom I want to see.
(3) The man who/whom you met just now is my friend.
(1) Football is a game which is liked by most boys.
(2) This is the pen (which) he bought yesterday.
He is the man whom/who I talk to.
He is the man who has an English book.
(5) The number of the people that/who come to visit the city each year rises one million.
(6) Where is the man that/whom I saw this morning?
(1) He has a friend whose father is a doctor.
(2) I once lived in a house whose roof has fallen in.
(3) The classroom whose door is broken will soon be repaired.
(4) The classroom the door of which is broken will soon be repaired.
(5) Do you like the book whose cover is yellow?
(6) Do you like the book the color of which is yellow?
(1) The school (that/which) he once studied in is very famous.
(2) The school in which he once studied is very famous.
(3) Tomorrow I will bring here a magazine (that/which) you asked for.
(4) Tomorrow I will bring here a magazine for which you asked.
(5) We’ll go to hear the famous singer (whom/that/who) we have often talked about.
(6) We’ll go to hear the famous singer about whom we have often talked.
1. 含有介词的动词短语一般不拆开使用，如：look for, look after, take care of等
(1) This is the watch which/that I am looking for. (T)
(2) This is the watch for which I am looking. (F)
(1) The man with whom you talked is my friend. (T)
(2) The man who/that you talked with is my friend. (F)
(3) The plane in which we flew to Canada is very comfortable. (T)
(4) The plane in that we flew in to Canada is very comfortable. (F)
3. “介词+关系代词”前可有some, any, none, both, all, neither, most, each, few等代词或者数词
(1) He loved his parents deeply, both of whom are very kind to him.
(2) In the basket there are quite many apples, some of which have gone bad.
(3) There are forty students in our class in all, most of whom are from big cities.
(1) I still remember the day when I first came to the school.
(2) The time when we got together finally came.
(1) Shanghai is the city where I was born.
(2) The house where I lived ten years ago has been pulled down.
(1) Please tell me the reason why you missed the plane.
(2) I don’t know the reason why he looks unhappy today.
(1) The reason why/ for which he refused the invitation is not clear,
(2) From the year when/in which he was going to school he began to know what he wanted when he grew up.
(3) Great changes have taken place in the city in which./where I was born.
形式上 不用逗号和主句隔开 用逗号和主句隔开
意义上 是先行词不可缺少的定语，不能删除 是对先行词的补充说明，删除后意思仍完整
译法上 翻译成先行词的定语，“…的…” 通常翻译成主句的并列句
关系词的使用上 A．做宾语时可省略 B。可用that
C．可用who代替whom A．不可省 B。不用that
(1) The teacher told me that Tom was the only person that I could depend on.
(2) China is a country which has a long history.
(1) His mother, who loves him very much, is strict with him.
(2) China, which was founded in 1949, is becoming more and more powerful.
(1) His brother who is now a doctor always encourages him to go to college.
(2) His brother, who is now a doctor, always encourages him to go to college.
This is the mountain village where I stayed last year.
I'll never forget the days when I worked together with you.
（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) 。
3） 某些在从句中充当时间，地点或原因状语的"介词+关系词"结构可以同关系副词when 和where 互换。
This is the house in which I lived two years ago.
This is the house where I lived two years ago.
Do you remember the day on which you joined our club?
Do you remember the day when you joined our club?
1)Whoever spits in public will be punished here.
(Whoever 可以用 anyone who 代替)
2)The parents will use what they have to send their son to technical school.
(what 可以用all that代替)
as, which 非限定性定语从句
由as, which 引导的非限定性定语从句，as和which可代整个主句，相当于and this或and that。As一般放在句首，which在句中。
As we know, smoking is harmful to one's health.
The sun heats the earth, which is very important to us.
1）Alice received an invitation from her boss, ___came as a surprise.
A. it B. that C. which D. he
答案C. 此为非限定性从句，不能用 that修饰，而用which.，it 和he 都使后句成为句子，两个独立的句子不能单以逗号连接。况且选he句意不通。
2）The weather turned out to be very good, ___ was more than we could expect.
A. what B. which C. that D. it
3）It rained hard yesterday, ____ prevented me from going to the park..
A. that B. which C. as D. it
(1） as 引导的定语从句可置于句首，而which不可。
(2） as 代表前面的整个主句并在从句中作主语时，从句中的谓语必须是系动词；若为行为动词，则从句中的关系代词只能用which.。
例1. the same… as；such…as 中的as 是一种固定结构, 和……一样……。
I have got into the same trouble as he (has).
As we know, smoking is harmful to one's health.
As is know, smoking is harmful to one's health.
(错) The tree, that is four hundred years old, is very famous here.
We depend on the land from which we get our food.
We depend on the land that/which we get our food from.
a) 在there be 句型中，只用that，不用which。
b) 在不定代词，如：anything, nothing, the one, all, much, few, any, little等作先行词时，只用that，不用which。
c) 先行词有the only, the very修饰时，只用that。
All that is needed is a supply of oil.
Finally, the thief handed everything that he had stolen to the police.
1．当先行词是anything, everything, nothing (something 除外), few, all, none, little, some等代词时，或者是由every, any, all, some, no, little, few, much等修饰时
(1) Have you taken down everything that Mr. Li has said?
(2) There seems to be nothing that seems impossible for him in the world.
(3) All that can be done has been done.
(4) There is little that I can do for you.
(4) Any man that/.who has a sense of duty won’t do such a thing.
(1) The first place that they visited in London was the Big Ben.
(1) This is the best film that I have seen.
4. 当形容词被the very, the only 修饰时
(1) This is the very good dictionary that I want to buy,
(2) After the fire in his house, the old car is the only thing that he owned.
(3) Wang Hua is the only person in our school who will attend the meeting/
5. 当先行词前面有who, which等疑问代词时
(1) Who is the man that is standing there?
(2) Which is the T-shirt that fits me most?
(1) Can you remember the scientist and his theory that we have learned?
(1) He married her, as/which was natural.
(2) He was honest, as/which we can see.
2. as 引导非限制性定语从句，可放在主句之前，或者主句之后，甚至可以切割一个主句；which引导的非限制性定语从句只能放在主句之后。另外，as有“正如……，正像……”的意思
(1) As is known to all, China is a developing country.
(2) He is from the south, as we can see from his accent.
(3) John, as you know, is a famous writer.
(4) He has been to Paris more than several times, which I don’t believe.
(5) Tom was always late for school, which made his teacher angry.
3. 当先行次受such, the same修饰时，常用as
(1) I have never heard such a story as he tells.
(2) He is not such a fool as he looks.
(3) This is the same book as I lost last week.
(4) She wore the same dress that she wore at Mary’s wedding. 她穿着她在MARY婚礼上穿过的一条裙子。
(5) She wore the same dress as her young sister wore. 她穿着和她妹妹所穿的一样的裙子。
（三）以the way为先行词的定语从句通常由in which, that引导，而且通常可以省略。
(1) The way in which/ that/./ he answered the question was surprising.
(1) There are very few but understand his idea. ( but= who don’t )
(1) The plane that has just taken off is for London. 定语从句
(2) The fact that he has been dead is clear. 同位于从句
2．定语从句由关系代词或者关系副词引导，关系词在句中充当成分，有时可以省略；同位语从句主要由that引导，在句中一般不做成分；句子也可以由when, where, how, why, whether, what等词引导，充当成分
(1) The news he told me is true.
(2) The news that he has just died is true.
(3) The problem that we are facing now is how we can collect so much money. 定语
(4) The problem how we can collect so much money is difficult to solve.
(1) The idea that we could ask the teacher for advice is wonderful. 同位语
(2) The idea was that we could ask the teacher for advice.
(3) The fact that the earth moves around the earth is known to all.
(4) The fact is that the earth moves around the earth.