先行词 关 系 词 在 从 句 中 充 当 成 分
主 语 宾 语
（可省） 定 语 状 语
地 点 时 间 原 因 方 式
指 人 who
that
whom
who
that
whose
of whom
指 物 which
that
as
which
that
as
whose
of which
where
介词+ which
when
介词+which
why
介词+which
that
in which
省略
在定语从句中，当先行词指物时，下列情况的关系词宜用that而不用which:
§（1）先行词被①形容词最高级 ②序数词 ③数词几种词修饰或被 ④only、any、few、little、no、all、one of等修饰时。
（2）先行词为all、much、little、none、few、one、something、anything等不定代词时。
（3）先行词中既有人又有物时。
He was looking pleasantly at te children and parcels that filled his bus.
（4）先行词在主句中作表语关系词在从句中作表语时。
The village is no longer the one that was 5 years ago.
（5）当主句中含有疑问词which时。
Which are the books that you bought for me ?
宜用which而不用that的情况
§ （1）在非限制性定语从句中
（2）在关系词前有介词时
（3）当先行词本身是that时
（4）当关系词离先行词较远时
关系词who与that指人时，也有不同情况分别用不同的关系词
§（1）当主句是there be句型时，关系词用who。
（2）先行词是为anyone、those、someone、everyone、one等词时，关系词用who。
（3）当主句是who作疑问词时，关系词用that。
Who is that girl that is standing by the window?
（4）whom在从句中只作宾语，可被who取代。
§ whose作关系词既指人又指物，在从句中作定语。如：
Do you know Mr.Smith whose story is very moving ?
There is a room, whose window faces the river.
There is a room, the window of which faces the river.
关系代词as,在从句中作主语、宾语和表语。
§（1）关系代词常出现在the same…as, such…as, so…as, as…as 等结构中
This is not such a book as I expected.
I live in the same building as he (lives in).
Here is so big a stone as no man can lift.
As many children as came here were my father’s pupils.
★ the same…that…和the same…as…的区别
I have bought the same watch as you have.
我买了一块和你一样的手表。（我的手表和你的手表很像，但不是同一块。）
This is the same watch that I lost.
这就是我丢的那块手表。（这手表和我丢的手表是同一块）
§ （2） as引导非限制性定语从句，指代逗号前的整个句子（即先行词），可置于句首或句末。
This elephant is like a snake, as anybody can see.
Mary was late for school, as often happened.
As is known to all, the earth is round.
★ as 指代一句话和which 指代一句话的用法区别
which则不需要，例如：
The man died last night, which is a lie.
as 替代一句话即可放句首也可放句末，而which只能放句末。1）先行词被such和the same修饰，或句型as many（much）中，从句都用as 引导。
Such books as you bought are useful.
The school is just the same as it was 10 years age.
注意：区别①such … that … 引导的结果状语从句。They are such
lovely children that we love them much.
§ ②the same … that … 引导定语从句。I want to use the same tool that you used just now
§ （2）无先行词的定语从句用as和which引导。
区别：①意义上：as 含有“这点正如……一样”。②位置上：as 从句可置句首，也可在另处。
He didn’t pass the exam, as we had expected.
There is lots of air in loose snow, which can keep the cold out.
As is known, the earth is round, not flat.
关系副词when与where、why, how, that (非正式)
§ when 指时间 = in / at / on / during which
where指地点 = in / at / from / which
why指原因 = for which
§ How指方式= by which
当先行词为way、day、reason、time时，可用that作关系副词。（非正式场合）
I don’t like the way that / in which / he talks.
§ that可以用于表示时间、地点、方式、理由的名词后取代when, where, why和"介词+ which"引导的定语从句，在口语中that常被省略，例如：
His father died the year (that / when / in which) he was born.
当time作先行词时，关系词可以省掉。
This is the first time I have given you a lesson in French.
必须注意的问题
§ （1）、关系代词在定语从句中主语，其谓语动词与先行词保持一致。例如：
The boy who is standing at the door is my son.
§ 在one of the +复数名词+定语从句结构中，复数名词是先行词，关系代词在定语从句中作主语，其谓语动词用复数形式。例如：
This is one of the best books that have ever been written on the subject.
§ 在“the only one of the +复数名词+定语从句”结构中，one 是先行词，关系代词在定语从句中作主语，其谓语动词用单数。例如：
This is the only one of the best books that has ever been written on the subject.
区别定语从句与强调句
§ ①定语从句中关系词作从句成分，复合句。
②强调it无意义，that / who不是引导词。
③强调it is / was和that / who后如果句子意思讲得通则是强调句，讲不通则不是。
It is the museum that is near school.(定语从句)
It was in the hotel that we stayed last night.（强调句）
§ ——He was nearly drowned once.
——When was _______?
——____ was in 1998 ______he was in middle school.
A. that; It; when B. this; This; when C. this; It; that D. that; It; that
[简析]：本题答案为A。由于定语从句的干扰作用，相当一部分考生选了D。这样就成了It was in 1998 that he was in middle school.这样就成了一个强调句型，意为“是在1998年他上的中学”，孤立地看本句虽成立，但联系上下文来看，却属“所问非所答”。因为上文问的是“他何时差点每被淹死？”而非“何时上的中学”。原来when是关系副词，引导定语从句，修饰1998。定语从句when he was in middle school 干扰了强调句型中的that结构。
定语从句与同位语从句的区别
§定语从句与前面的名词是修饰与被修饰的关系“。。。的（名词）”。而同位语从句是用来说明前面名词的内容。与that从句同位的名词必须是一些表事实或概念的抽象名词，如fact, news, belief, truth, reply等。that在定语从句中作成分，可用which 或who/whom代替；而that在同位语从句中不充当任何句子成分，只起连接作用。
Word came that their army was defeated.(同位语)
We expressed to them our wish that was the same as their.(定语)
§ We all have heard the news that our team won. (同位语从句，that从句表示news的内容，that 在从句中不作任何成分)
We don’t believe the news that/which he told us yesterday.
定语从句与状语从句
§ ① He left the key where he had been an hour before.
(where引导地点状语从句，相当于in the place where)
② He left the place where he lived for many years.
(where 引导定语从句，修饰the place)
③ He is such a good teacher as all of us love and respect.
(as 引导定语从句)
④ He is such a good teacher that we all like him.
(that引导结果状语从句,such…that… “如此…以致…”
定语从句与主语从句
§ ① As is known to us all, paper was first made in China.
(as 引导定语从句，指代整个主句内容，可置于句首)
② It is known to us all that paper was first made in China.
(it 做形式主语，代替that 引导的主语从句)
关系词在从句中省略的情况
§ ①关系词作宾语，前无介词时。
②关系词作表语。
（5）限制性定语从句与非限制性定语从句的翻译。
（6）关系词前有介词或复杂介词，关系词只能是which和whom。
判断关系代词与关系副词
§ 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：
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.
方法二： 准确判断先行词在定语从句中的成分(主、谓、宾、定、状)，也能正确选择出关系代词/关系副词。
§ 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)
练习题
§ 1. The factory __________ his mother works is in the east of the city.
§ A. that B. which C. on which D. where
§ 答案：D．关系副词where 在定语从句中作地点状语．
§ 2. The place __________ interested me most was the Children’s Palace.
§ A. which B. where C. what D. in which
§ 答案：A．关系代词which代the place , 在定语从句中作主语，所以不能选B，D．如不用Ｔhe place 就选C，主语从句．
§ ＊归纳：在学习定语从句时不要一看到表示地点的字眼就选where或in which等。
§ 3. Please make a mark ________you don’t understand.
§ A. where B. in which C. at which D. that
§ 答案：A．where引导地点状语从句。
§ 4. They talked of things and persons ________they remembered in the school.
§ A. that B. \ C. whom D. both A and B
§ 答案 D先行词为things and persons 为人和事，只能用that ,因为作宾语，故可省。
§ 5. All ________has to be done every day is to listen and to repeat what he does.
§ A. that B. which C. whom D. he
§ 答案 A 先行词all 为不定代词，只能用that ,不能用which.此外还有先行词为anything, everything, nothing, any ,little, one, few, much, none等，如：（1） There isn’t much that I can do. （2） He is one of the few that can work it out in five minutes.
§ 6. This is the biggest library ______ we have ever built in our university.
§ A. which B. where C. that D. one
§ 答案 C 当先行词由形容词最高级或被形容词最高级修饰时用that.
§ 7 This is the first place _______I’ve ever visited.
§ A. where B. in which C. that D. which
§ 答案 C 当先行词为序数词或被序数词修饰时用that.
§ 8. Is this the very museum ______ you visited the other day?
§ A. which B. that C. what D. where
§ 答案 B 当先行词被the very, the only 等修饰时用that
§ 9. She is wearing the same dress ______she wore yesterday.
§ A. like B. as C. that D. which
§ 答案 C 当先行词被the same 修饰，且指“同一物品”时用that.
§ 10. He is not the man _____ he was.
§ A. what B. that C. as D. who
§ 答案 B 关系代词在定语从句中作表语时用that.
§ 11. Which is the book ______you bought yesterday?
§ A. which B. that C. what D. the one
§ 答案 B 当主语从句是以who, which 开头的特殊疑问句或先行词是who 时用that.
§ 12. I have the same book _____you bought yesterday.
§ A. as B. that C. which D. what
§ 答案 A the same 与as 搭配，请与第九题比较。
§ 13. Do you have such a book ______ he has?
§ A. as B. that C. which D. what
§ 答案 A as 与关系代词such搭配
§ 14. _______ is known to all, the earth moves around the sun.
§ A. It B. As C. Which D. That
§ 答案 B 关系代词 as 引导非限定性定语从句，带地球绕月亮转这件事，表“正如”。不可用which
§ 15. _______ is known to all that the earth moves around the sun.
§ A. It B. As C. Which D. That
§ 答案 A It 为形式主语，不可用that.
§ 16. He was late this morning, _______made the teacher angry.
§ A. that B. which C. as D. what
§ 答案为B which用于非限定性定语从句，无先行词，代替“他迟到”这件事。不用as 因为无“正如”的意思。
§ 17. Soon we arrived at the school, in front of _____ grew a lot of flowers.
§ A. it B. that C. where D. which
§ 答案D 关系代词前用介词或短语介词指物品时只能用which.
§ 18. He wrote several songs last year, and three of _____ were very popular among young people.
§ A. them B. which C. what D. that
§ 答案 A 此句不是从句，而是用and 连接的并列句，故用them.
§ 19. Soon we came to a small house; ______stood a very tall tree.
§ A. in front of that B. in front of it C. in front of which D. in the front of it
§ 答案 B 因为前面用“；”，前后两个是独立单句，不能用关系代词。
§ 20.T he stories about the Long March, _____this is one example, are well written.
§ A. for which B. of which C. that D. what
§ 答案 B one example of the stories
§ 21. The old man has a daughter, _____a better daughter does not exist.
§ A. of which B. with whom C. whose D. than whom
§ 答案 D 定语从句为 a better daughter than whom does not exist.为了句子结构严谨，than whom调到定语从句前。
§ 22. Do you remember the day _____we spent _____climbing Mount Tai last summer?
§ A. \; going B. when; in going C. on which; going D. which; to go
§ 答案A 关系代词作宾语时可省去，前空可用that, which 或\，后空可用going 或in going.
§ 23. I’ll never forget the days ____ we played together in our childhood.
§ A. which B. that C. \ D. when
§ 答案 D 因为play 为不及物动词，可用on which 或when .
§ 24. The reason _____ he was late was _____he got up too late.
§ A. why, that B. that, why C. why, because D. that, because
§ 答案 A He was late for the reason . for the reason 用关系副词why来代替,后面用that 引导表语从句，不能用 because.
§ 25. The reason______ he told us sounds reasonable.
§ A. that B. which C. why D. for which
§ 答案 A 句子结构为he told us the reason , 关系代词that 作 told 的直接宾语。
§ 26. The news ______ he has won the medal is true
§ A. that B. which C. \ D. what
§ 答案 A that 连接同位语从句，而不是定语从句。
§ 27. The news______ he told us is not true. Which is not right?
§ A. that B. which C. \ D. what
§ 答案为D，这是定语从句，关系代词which或that作told的宾语也可省
§ 28. The house _____ have been broken _____to be repaired.
§ A. which windows, needs B. whose window, needs
§ C. the window of it, need D. the windows of which, needs
§ 答案 D 可用D 或windows ， 但不可用which windows.
§ 29. The children ____ parents died has just been sent to an orphan’s house.
§ A. his B. that C. whose D. which
§ 答案 C 不能用his ， 因为必须要关系代词引导定语从句。
§ 30. He is the only one of the students ______late this morning.
§ A. who is B. who was C. who are D. who were
§ 答案为 B 因为先行词为the only one ,故用单数。
§ 31. He is one of the teachers ___________ praised by the government at the meeting.
§ A. whom were B. who was C. whom was D. who were
§ 答案为D，关系代词who的先行词为the teachers为复数
§ 32. I, ______ your good friend, will try my best to help you out.
§ A. who is B. who am C. that is D. what is
§ 答案为B，因为关系代词who的先行词为I
§ 33. Is this book ______ you referred to at the meeting?
§ A. that B. which C. the one D. what
§ 答案为C， 本句无先行词，必须补上先行词the one，关系代词that作referred to的宾补，故可省
§ 34. Is this factory ______ his mother worked? Ten years ago. Which can’t be used?
§ A. the one B. where C. the one where D. the one in which
§ 答案为A， 用B，该句为表语从句，用C、D该句为定语从句
§ 35. Plants grow well ______ there is enough sunlight and water.
§ A. where B. in which C. in the place D. with
§ 答案为A，用where引导地点状语从句。
§ 36. I don’t like the way ______ you speak to your mother.
§ A. / B. in that C. which D. of which
§ 答案为A， 当定语从句的先行词是the way（方式）时，引导定语从句的关系词用in which/that，也可以省略。
§ 37. Is this the house ______ once Lu Xun lived in his childhood?
§ A. the one B. where C. which D. that
§ 答案为B，先行词为the house
§ 38. Has ______ must be done been done?
§ A. all B. all that C. that D. it
§ 答案为B， 也可用what连接主语从句，all that为定语从句
§ 39. Those foreign teachers, most of ______ have never been to china before, are enjoying their work have very much.
§ A. who B. whom C. them D. that
§ 答案为B， most of whom为主语，但whom作介词of的宾语。
§ 40. ______ you met Mr. Green for the first time?
§ A. where it was that B. was it where that C. where was it that D. where was it where
§ 答案为C，应为强调句，对It was in the street that you met ….进行提问即可得到。
§ 41. The factory was built in a secret place, around ______ high mountains.
§ A. which was B. it was C. which were D. them were
§ 答案是C，around which were high mountains 是一个由“介词+which”引出的非限制性定语从句，而在该从句中，主语是 high mountains，around which 是表语，所以句子谓语应用复数were，而不是用单数 was.
§ 42. A man with a bleeding hand hurried in and asked, “Is there a hospital around ______ I can get some medicine for my wounded hand？”
§ A. that B. which C. where D. what
§ 答案为C。若选A此句的意思即为：有没有这样一个医院，我在它的附近可以买药治我的手伤？这样的语境显然有点不合情理，因为人们通常是在医院里面治伤，而不是在医院附近治伤。此题选 C 的理由是：句中的 around 不是介词，而是副词，意为“在附近”；其后的 where 引导定语从句用以修饰其前的地点名词 hospital，句意为：附近有没有一家医院，我可以去治我的手伤？
§ 43. _____ is known to everybody, the moon travels round the earth once every month.
§ A. It B. As C. That D. What
§ 答案是 B。as 引导的是一个非限制性定语从句。
§ 44. David is such a good boy _______ all the teachers like.
§ A. that B. who C. as D. whom
§ 答案为C，因为在such … that … （如此……以至……）结构中，that 引导的是结果状语从句，并且 that 在从句中不充当句子成分，若在上句填入 such … that …，句末的动词 like 缺宾语。选C的理由如下：as 用作关系代词，用以引导定语从句，修饰其前的名词 boy，同时 as 在定语从句中用作动词 like 的宾语，句意为“所有老师都喜欢的一位好男孩”。有的同学可能还会问，假若选A，能否将其后的 that 视为引导定语从句的关系代词呢？不能，因为当先行词受到 such 的修饰时，其后的定语从句应用关系代词 as 来引导，而不用that.比较下面一题，答案为A，因为 like 后有自己的宾语 him：
§ 45 He told me that he had two girl-friends, neither of _______ knew anything about the other.
§ A. whom B. them C. which D. who
§ 答案为A。
§ 46.He told me that he had two girl-friends, and neither of _______ knew anything about the other.
§ A. them B. whom C. which D. who
§ 答案为A。
§ 47. He had a lot of friends, only a few of ______ invited to his wedding.
§ A. whom B. them C. which D. who
§ 答案是B，这不是非限制性定语从句，而是一个独立主格结构，因为空格后的动词 invited 并不是一个完整的谓语，而是一个过去分词。当然，假若在 invited 前加上助动词 were，则是一个非限制性定语从句，答案便应选A.比较：
§ 48. On Sundays there were a lot of children playing in the park, _______ parents seated together joking.
§ A. their B. whose C. which D. that
§ 答案是A.与上面一题相似，their parents seated together joking 不是非限制性定语从句，而是一个独立主格结构，因为空格后的动词 seated 不是谓语，而是一个过去分词，因为 seat 作动词用时，是及物动词。比较以下相似题：
§ 49. On Sundays there were a lot of children playing in the park, _______ parents were seated together joking.
§ A. their B. whose C. which D. that
§ 选B.whose parents were seated together joking 为非限制性定语从句，因为其后有完整的谓语 were seated.
§ 50. On Sundays there were a lot of children playing in the park, and _______ parents were seated together joking.
§ A. their B. whose C. which D. that
§ 选A.因为句中有并列连词and，整个句子为并列句。
§ 51. On Sundays there were a lot of children playing in the park, _______ parents sitting together joking.
§ A. their B. whose C. which D. that
§ 选A.their parents sitting together joking 为独立主格结构。
§ 52. On Sundays there were a lot of children playing in the park, _______ parents sat together joking.
§ A. their B. whose C. which D. that
§ 选B.whose parents sat together joking 为非限制性定语从句，因为句中有完整的谓语 sat.
§ 53. On Sundays there were a lot of children playing in the park, _______ parents were sitting together joking.
§ A. their B. whose C. which D. that
§ 选B.whose parents were sitting together joking 为非限制性定语从句，因为句中有完整的谓语 were sitting.
§ 54．If the man is only interested in your looks, _____ just shows how shallow he is.
§ A. as B. which C. what D. that
§ 答案为D，注意逗号前是一个条件状语从句，逗号后是该状语从句的主句，that 在此代表前文所述的情况，用作主句的主语。类似地，下面几道题也选 that，而不选 which：
§ （1） If you promise to go with us, _____ will be OK.
§ A. as B. which C. and it D. that
§ （2） Whether you go or not, _______ is quite all right with me.
§ A. that B. which C. and it D. so
精编陷阱题训练
§ 1. All of the flowers now raised here have developed from those _______ in the forest.
§ A. once they grew B. they grew once C. they once grew D. once grew
§ 2. In the office I never seem to have time until after 5：30 pm, _____ many people have gone home.
§ A. that B. which C. whose time D. by which time
§ 3. Is this the reason _______ at the meeting for his carelessness in his work？
§ A. he explained B. what he explained C. how he explained D. why he explained
§ 4. Luckily, we’d brought a road map without ______ we would have lost our way.
§ A. it B. that C. this D. which
§ 5. When he was working there he caught a serious illness from _____ efforts he still suffers.
§ A. which B. that C. whose D. what
§ 6. It’s said that he’s looking for a new job, one ______ he can get more money to support his family.
§ A. when B. where C. that D. which
§ 7. We are living in an age ______ many things are done on computer.
§ A. which B. that C. whose D. when
§ 8. The little time we have together we’ll try _____ wisely.
§ A. spending it B. to spend it C. to spend D. spending that
§ 9. The old building, behind _______ was a famous church, was _______ we used to work.
§ A. that, the place B. it, the place C. which, where D. what, where
§ 10. We will be shown around the city： schools, museums, and some other places, _______ other visitors seldom go.
§ A. what B. which C. where D. when
§ 11. The modern history of Italy dates from 1860, ______ the country became united.
§ A. when B. if C. since D. until
§ 12. All of the flowers now raised here have developed from those _____ in the forest.
§ A. once they grew B. they grew once C. that once grew D. once grew
§ 13. You could see the runners very well from ______ we stood.
§ A. which B. where C. that D. when
§ 14. Recently I bought an ancient Chinese vase, _______ was very reasonable.
§ A. which price B. the price of which C. its price D. the price of whose
§ 15. What have you got _____ will help a cold？
§ A. what B. that C. it D. who
16. He was very angry and I can still remember the way _____ he spoke to me.
§ A. how B. that C. what D. which
§ 17. Do you know the man from ________ house the pictures were stolen？
§ A. which B. that C. what D. whose
§ 18. I can think of many cases _______ students obviously knew a lot of English words and expressions but couldn’t write a good essay.
§ A. why B. which C. as D. where
§ 19. Is this all that you need？ If you married me, I’d give you everything you _____.
§ A. want B. wanted C. had wanted D. are wanting
§ 20. I met the teacher in the street yesterday ________ taught me English three years ago.
§ A. which B. when C. where D. who
§ 21. He’s got himself into a dangerous situation _____ he is likely to lose control over the plane.
§ A. where B. which C. while D. why
§ 22. He made another wonderful discovery, ______ of great importance to science.
§ A. which I think is B. which I think it is C. which I think it D. I think is
§ 23. Dorothy was always speaking highly of her role in the play, ____, of course, made the others unhappy.
§ A. who B. which C. this D. what
§ 24. Their problem today is somewhat similar to _____ they faced many years ago.
§ A. that B. which C. that which D. it
§ 25. I saw some trees the leaves of _____ were black with disease.
§ A. that B. which C. it D. what
§ 26. The famous basketballer, _______ tried to make a comeback, attracted a lot of attention.
§ A. where B. when C. which D. who
§ 27. When they went into the shop and asked to look at the engagement rings, the girl brought out a cheaper one, _______ she had arranged with James.
§ A. the which was what B. what was that C. which was what D. that was that
答案与解析◆
§ 1. 选 C.先行词是 those，可视为 those flowers 之省略。they once grew 前省略了关系代词 which.全句意为：这儿所养的花是由他们曾在森林里种植的花培养出来的。
§ 2. 选D.by which time 引出的是一个非限制性定语从句，其中 by which time 相当于 and by that time.
§ 3. 选 A.注意不能选 D，因为动词 explained 缺宾语。
§ 4. 选 D.which 指 the road map.
§ 5. 选C.from whose efforts he still suffers 为修饰 a serious illness 的定语从句，whose 在定语从句中用作定语，修饰 efforts.
§ 6. 选B.where 引导定语从句修饰 one.注：one 在此指 a new job.类似地，下面一题的答案是C，因为one that 相当于 a problem that：
§ The problem is _____ has caused us a lot of trouble.
§ A. one B. that C. one that D. that one
§ 7. 选 D.先行词是表时间的 age（时代），由于关系词在定语从句中作状语，故用 when.
§ 8. 选C.该句的正常词序为 We will try to spend the little time we have together wisely.
§ 9. 选C.第一空填 which，指 the old building；第二空填 where，用以引导表语从句。
§ 10. 选 C.先行词是地点名词 places，由于关系词在定语从句中作状语，故用 where.
§ 11. 选A.when 引导的是非限制性定语从句。
§ 12. 选C.that once grew in the forest 为修饰 those 的定语从句。
§ 13. 选B.where 在此相当于 the place where.
§ 14. 选 B.the price of which was very reasonable 为非限制性定语从句，其中的 the price of which 相当于 and its price 或 and the price of it.假若空格前有并列连词 and，则可选 C.
§ 15. 选B.that will help a cold 为修饰 what 的定语从句。比较：Have you got anything that will help a cold？ 以及 I’ve got nothing that will help a cold.
§ 16. 选B.the way 后不接how 引导的从句，换句说，how 不是关系代词或关系副词，不能引导定语从句。以the way 为先行词的定语从句通常用 that 或 in which 来引导，在非正式文体中也可省略 that 和 in which.
§ 17. 选D.from whose house the pictures were stolen 为修饰 the man 的定语从句，whose 在定语从句中用作定语，修饰 house.
§ 18. 选 D.先行词是 many cases，关系副词 where =in which.
§ 19. 选A.尽管句中用了 if you married me, I’d give you everything 这样的虚拟语气句子，但修饰everything 的定语从句 （that） you want 却要用陈述语语气，因为它是回答前面 Is this all that you need？ 这一提问的。
§ 20. 选 D.因定语从句缺主语，且关系代词指人，故选D.
§ 21. 选A.where 所引导的为修饰 a dangerous situation 的定语从句。
§ 22. 选 A.选项中的 I think 是插入语，若略去不看便可清楚地看出答案。
§ 23. 选 B.of course 为插入语，若将项其去掉，则答案显然是B.
§ 24. 选C.that which相当于 the problem which.
§ 25. 选B.the leaves of which 相当于 whose leaves.
§ 26. 选 D.先行词是 The famous basketballer（著名的篮球明星），故要用 who 来引导定语从句，因为其余三项均不用于指人。
§ 27. 选 C.which 引导一个非限制性定语从句，其中 which 指代 a cheaper one，且在定语从句中用作主语。which was what 中的 what引导一个表语从句，它相当于 the one that.
本文来源：https://www.2haoxitong.net/k/doc/0db39f691eb91a37f1115cf2.html
文档为doc格式