引导定语从句的关系副词有when, where或 why等。when, where, why分别在定语从句中作状语，在意义上相当于介词+which结构，分别代替表示时间、地点或原因的先行词。

　 A．when　

　 指时间，在定语从句中作时间状语。

　 I still remember the day when I first came to this school.

　 我仍然记得我第一次来到这所学校的那一天。(when= on which)

　 He came at a time when we needed him most.

　 他是在我们最需要他的时候来的。(when= at which)

　 We will never forget the year 1949, when th People's Republic of China was founded.

　 我们永远忘不了1949年，那是中华人民共和国成立的一年。(when= in which)

B．where　

　 指地点，在定语从句中作地点状语。

　 I recently went back to the town where I was born.

　 我最近曾回过一次我出生的城市。(where = in which)

　 I would like to live in a country where there is plety of sunshine.

　 我想住在一个阳光充足的国家。(where = in which)

　 What's the name of the place where you spent your holiday

　 你度假的那个地方叫什么名字？(where = at which)

C．why　

　 指原因，在限制性定语从句中作原因状语。

　 Please tell me the reason why you missed the plane.

　 请告诉我你误机的原因。(why = for which)

　 Te reason why he was punished is unknown to us.　

　 他受惩罚的原因我们都不知道。

注意:

　 无论是关系代词，还是关系副词，都在定语从句中取代了先行词，因此，先行词在定语从句中不复出现。

[误]This is the book that I borrowed it yesterday.

[正]This is the book that I borrowed yesterday.

　　 这就是我昨天借的书。(that在定语从句中取代了先行词the book，作borowed的宾语，因此，要去掉it)

[误]The English Corner is the place where people often go there to practise their spoken English.

[正]The English Corner is the place where people often go to practise their spoken English.

　　 英语角是人们经常去练习英语口语的地方。(where在定语从句中取代了先行词the pace，作go的状语，因此，要去掉there)

3．关系代词前介词的选择

　 在介词+关系代词引导的定语从句中，应注意介词的正确选择。

　 ①　 根据后面动词和介词的搭配关系选择。

　 The two things of which they felt prud were Jim's watch and Della's hair.

　 他们引以为豪的两样东西是吉姆的手表和德拉的头发。(feel proud of是固定搭配词组)

　 In the dark street there was not a single person to whom she could turn for help.

　 在漆黑的街道上没有一个她可以求助的人。(turn to sb. for help是固定搭配词组)

　 ②根据与前面名词的搭配关系选择。

　 I'll never forget the ay on which I first met him.

　 我永远忘不了我第一次遇见他的那一天。(the day前面一般用介词on)

　 Can you imagine a proper situation in which the expression can be used

　 你能设想一个使用这个词语的场合吗？(a situation前面一般用in)

　 ③有时须同时考虑动词和介词的搭配关系及介词和名词的搭配关系。

　 Galileo made a telescope through which he could tudy the sky.

　 伽里略制作了一个望远镜，通过它他得以研究天空。(study the sky through the telescope)

　 Is that the house in which you once lived

　 那就是你曾经住过的房子吗？(live in the house)

　 ④根据所要表达的意思来确定。

　 This is my pair of glasses, without which I cannot see clearly.

　 这是我的眼镜，离了它我什么也看不清。

注意：

　 当关系代词在定语从句中作主语时，谓语动词应与先行词的人称和数保持一致。

　 I, who am your best friend, will do all that I can to help you.

　 我是你的好朋友，我会尽我一切所能来帮你。

　 The family, who are fond of music, go to the concert once a month.

　 这家人很爱音乐，他们每月都去听一次音乐会。

　 He is one of the boys in ourclass who speak English well.

　 他是班上英语说得很好的男生之一。(one of +复数名词+关系代词引导的定语从句谓语动词用复数形式)

　 He is the only one of the boys in our class who speaks English well.

　 他是班上唯一英语说得很好的男生。(the (only) one　 the very one the right one of +复数名词+关系代词 引导的定语从句谓语动词用单数形式)

2．介词+关系代词的常见结构

　 ①介词+whichwhom

　 This is the famous singerabout whom we have often talked.

　 这就是那位我们经常谈论的著名歌唱家。

　 Fortunately we had a map, without which we would have got lost.

　 很幸运，我们带了一张地图，如没有的话，我们就会迷路了。

　 ②名词+of+ whichwhom

　 Please pass me the book the cover of which is blue. 请把那本蓝封面的书递给我。(也可用whose cover)

　 ③数词+o+ whichwhom

　 She's got three lucky pens, two of which she never uses.

　 她有三只幸运笔，其中两只从未用过。

　 In our school there are about 200 teachers, thirty percent of whom are women. 我校大约有200位教师，其中百分之三十是女教师。

　 ④代词+of+ whichwhom

　 In the basket I find many apples, some o which have gone bad.

　 我发现篮子里有好些苹果，有些已经坏了。

　 There are fifty students in our class, most of whom are from big cities.

　 我们班有50个学生，其中大多数来自大城市。

　 Norman won $50,000, half of which he gave to his parents.

　 诺曼赢得五万美元，他将其中一半给了他父母。

　 Tom tried on three shirt, none of which he was satisfied with.

　 汤姆试穿了三件衬衫，都不满意。

　 ⑤最高级+of+ whichwhom

　 China has thousands of islands, the largest of which is Taiwan. 中国有数千个岛屿，其中最大的是台湾。　

　 ⑥介词+which+名词

　 He usually returns home at ten, at which hour his father locks all the doors ad windows.

　 他通常十点钟回家，在这时候他爸爸锁好所有的门窗。

　 His wife got seriously ill, in which case he had to give up the chance of going abroad.

　 他的妻子病得很重，在这种情况下，他不得不放弃出国的机会。

1. 介词+关系代词中介词的位置

　 关系代词whom, which在从句中作介词宾语时，可以跟介词一起放在从句与主句之间(that, who不可以)，也可以把介词放在从句中有关动词的后面，使关系代词紧跟它所修饰的先行词。

　 He is a man of rich experience, from whom much canbe learned.　

　 = He is a man of rich experience, whom much can be learned from.

　 他是个经验丰富的人，从他那儿可以学到很多。

　 The school in which he once worked is a key school.　

　 =The school (which　 that) he once worked in is a key school.

　 他曾经工作过的学校是一所重点学校。

　 The manager in whosecompany I work pays much attention to improving our working conditions.

　 =The manager whose company I'm working in pays much attention to improving our working conditions.

　 我就职的那家公司经理十分注意改善我们的工作条件。

2．but

　 but作关系词只能引导限制性定语从句，同具有否定意思的主句连用，相当于that?not, who?not或which?not。

　 There is not a single student in my class but would like to study more.

　 我班上没有一个学生不愿意多学一点的东西的。(but = who?not )

　 There are very few but are against war　

　 很少人不反对战争。(but = who?not)

G．介词+关系代词引导的定语从句

　 介词+关系代词引导的定语从句是一种非常常见但也比较复杂的定语从句结构。

1．as

　 as可以在限制性定语从句和非限制性定语从句中作主语或宾语。

　 ① 在限制性定语从句中，as可跟在由suc, so, the same修饰的先行词之后。

　 Such men as heard him were deeply moved.

　听过他说话的人，都会深受感动。(as在定语从句中作heard的主语)

　 I've never heard such stories as he tells.

　 我从未听过像他讲的这样的故事。(as在定语从句中作tell的宾语)

　 He lifted so heavy a stone as no one else can lift.

　 他搬起别人都搬不起的大石头。(as在定语从句中lift的宾语)

比较：

　 在the same?as结构中，as也可用that代替。但严格地说，the same?as强调相同，the same?that注重同一。

　 She wore the same dress as her younger sister wore.

　 她穿着跟她妹妹所穿的一样的衣裙。(as指的是与先行词相似的同类事物)

　 She wore the same dress that she wore at Mary's wedding.

　 她穿着她在玛丽婚礼上穿过的同一条连衣裙。(that指的是与先行词同一事物)

　 ②　 在非限制性定语从句中，as可代表主句整个句子，引导的定语从句可以放在主句之前或主句之后，一般用逗号与主句分开。

　 As everyone knows, Taiwan belongs to China.

　 众所周知，台湾属于中国的领土。

　 He is from the outh, as we can know from his accent.

　 他是南方人，这一点我们从他的口音可以知道。

必背：

　 一些由as引导的定语从句常位于句首，已形成了固定的说法。

　 as is known to all

　 这是众所周知的

　 as has been said before

　 如前所说　

　 as is often the case

　 情况常常如此　

　 as may be imagined

　 这可以想象得出　

　 as has been pointed out

　 正如已经指出的那样　

　 as often happens

　 这种情况常常发生　

3．which在非限制性定语从句中有时也可以作定语。

　 John stayed here for a week, dring which time we visited the West Lake together.

　 约翰在这里呆了一星期，在此期间我们一起游了西湖。

　 It might snow this weekend, in which case we won't go to Beijing.

　 周末可能下雪，在这种情况下，我们就不去北京了。

　E．that

　 指人时，相当于who 或whom；指物时，相当于which。在定语从句中作主语或宾语(做宾语时常可省略)。

　 He is the man that lives next door.

　 他就是住在隔壁的那个人。(定语从句修饰先行词the man，作主语)

　 I don't like stories that have unhappy endings.

　 我不喜欢结尾悲伤的故事。(定语从句修饰先行词stories，作主语)

　 The dress (that) Ann boughtdoesn't fit her very well.

　 安买的衣服不太合身。(定语从句修饰先行词the dress，that作宾语可省略)

　 Is there anything (that) I can do for you

　 有我能为你效劳的事吗？(定语从句修饰先行词anything，that作宾语，可省略)

提示：

　 在口语中，that有时还可以作关系副词，相当于when或介词+which结构。

　 We left the day (that) he arrived. 他来的那一天，我们就走了。(that替when)

　 He doesn't see things the way (that) we see them. 他看问题的方法和我们不一样。(that代替in which)

　 Imagine the speed (that) he drives his car! 很难想象，他开车的速度那么快！(that代替at which)

F．其他关系代词

　 as 和but也可作关系代词，引导定语从句。

2．which引导的非限制性定语从句可以修饰前面的整个主句，相当于and this。

　 Jim passedhis driving test, which surprised everybody.

　 吉姆通过了驾驶考试，这使大家都感到惊讶。(定语从句修饰的是整个主句，而不是the driving test)

　 Sheila couldn't come to the party, which was a pity.

　 希拉不能来参加聚会，真遗憾。(定语从句修饰的是整个主句，而不是the party)

引导定语从句的关系代词主要有who, whom, whose, which, that等。它们分别代替前面的先行词，并在定语从句中作主语、宾语或定语。

　 A．who

　指人，在定语从句中作主语。

　 What was the name of the man who lent you the money

　 借钱给你的那人叫什么名字？(定语从句修饰先行词the man)

　 He who laughs lst laughs best.

　 谁笑到最后谁笑得最好。(定语从句修饰先行词he)

　 The chairman of the meeting, who spoke first, sat on my right.

　 会议主席坐在我右边，他先发言。(定语从句修饰先行词the chairman)

　 B．whom

　 指人，在定语从句中做宾语。在口语或非正式文体中，whom可省略或可用who来代替，但在介词后面以及在非限制性定语从句中只能用whom。

　 There are some people (whomwho)we like and others (whomwho) we dislike.

　 有些人我们是喜欢的，有些人则是我们讨厌的。(定语从句分别修饰先行词people, others)

　 The people whomwho I work with are all friendly.

　 和我一起工作的人都很友好。(定语从句修饰先行词the people)

　 Mr Carter, whom I spoke to on the phone last night, is very interested in or plan.

　 昨晚我在电话里和卡特先生交谈过，他对我们的计划很感兴趣。(非限制性定语从句中不能用who代替whom)

　 Two men, neither of whom I had ever seen before, came into my office.

　 两个人来到我的办公室，我以前从未见过他们。(在介词后面不用who)

　 C．whose　

　 通常指人，也可指物，在定语从句中做定语，后面要紧跟被修饰的名词。

　 There are some people whose faces you can nevr forget.

　 有些人，他们的脸你永远难以忘怀。(定语从句修饰先行词people)

　 I saw some trees whose leaves were black because of the polluted air.

　 我看见一些树的树叶由于空气污染而发黑。(定语从句修饰行词trees)

　 D．which

1．指物，在定语从句中做主语或宾语。做宾语时常可省略。

　 English is a language which is easy to learn.

　 英语是一门容易学的语言。(which在定语从句中作主语，不能省略)

　 This is a folk song which is now very popular.

　 这是目前非常流行的一首民谣(which在定语从句中作主语，不能省略)

　 The river which flows through London is the Thames.

　 流经伦敦的河叫泰晤士河。(which在定语从句中作主语，不能省略)

　 The children like cookies (which) my wife makes.

　 孩子们喜欢我夫人做的饼干。(关系代词which作makes的宾语，可以省略)

21．(本小题满分14分)已知圆C：，

(1)求出此圆圆心C的坐标和半径r；

(2)求直线y=x被圆C所截得的弦长.

附加题(满分15分)

已知函数，

(1)　　 求函数的定义域及值域；

(2)　　 判断该函数的奇偶性，并证明你的结论.