定语从句的关系代词
关系代词用来引导定语从句。它代表先行词，同时在从句中作一定的句子成分。关系代词有格的变化，并有指人与指物之分。
关系代词分类如下：
一、指人的关系代词。
主格——who，用在动词前，作主语。
属格——whose，用在名词前作定语。
宾格——whom，用在主语、谓语动词的前面，作动词或介系词的宾语。当介系词位于句子的末尾的时候，可以用who或whom来表示，但是如果把介系词提到从句之首，关系代词只能用whom。
The student who answered the question was Richard.
回答这个问题的同学是约翰。
I know a boy whose mother is a doctor.
我认识一位妈妈是医生的男孩。
The man whom she married was a teacher.
她嫁的那个人是一位教师。
The person of whom you are speaking is our principal.
你提到的那个人是我们的校长。
The person who you are speaking of is our principal.
你提到的那个人是我们的校长。
二、指物的关系代词。
主格——which，用在动词前，作主语。
属格——whose，用在名词前作定语。
宾格——which，用在主语、谓语动词的前面，作动词或介系词的宾语。我们把介系词提前，只能用which。
English is a language which is spoken all over the world.
英语是全世界通用的语言。
Look at that house whose roof was damaged.
看那幢屋顶受损的房子。
Remember the advice which I gave you.
记住我给你的那条忠告。
The train for which I am waiting is now half an hour late.
我在等的那班火车已经晚了半小时。
三、指人或物的关系代词。
主格——that，用在动词前，作主语。
属格——whose，用在名词前作定语。
宾格——that，用在主语、谓语动词的前面，作动词或介系词的宾语。
The boy that is playing the guitar is Richard.
正在弹吉他的男孩是理查德。
I like the building that was designed by Mr. Howell.
我喜欢那幢被毫尔先生设计出来的大楼。
He was looking for a car whose engine was in good condition.
他在找一辆引擎状况很好的车子。
The sandwiches that we ate for lunch weren't delicious.
我们午餐吃的三明治不好吃。
四、其它关系代词。
as，指前面的整个句子，可以作主语或宾语，如：
The earth is round, as is known to all.
人人皆知，地球是圆的。
The elephant is like a snake, as anybody can see.
任何人都能看见，大象就像条蛇。
than，用在比较句中，可以指代人或物。如：
You spent more money than was intended to be spent.
你花的钱超过了预定的数额。
but，表示否定，可以指代人或物。如：
There are no rules but have some exceptions.
凡规则皆有例外。
There is no mother but loves her children.
没有哪个母亲不爱自己的子女。
五、定语从句中关系副词的选用
⒈ when指时间,在定语从句中作时间状语,有时也可用介词+which来代替.
如：
I still remember the day when / on which I first came to Beijing.
我还记得我第一次来到北京那天的情景。
She came at a time when we needed her most.
她是在我们需要她的时候来的。
⒉ where指地点,在定语从句中作地点状语,有时也可用介词+which来代替。
如：
That is the house where/ in which he lived ten years ago.
那是他十年前住过的房子。
I have found a peaceful place where/ in which we can study.
我找到了一个能学习的安静的地方.
⒊ why指原因,在定语从句中作原因状语,常可用for+ which来代替.
如：
I know the reason why/ for which she was so angry.
我知道她为什么那么生气.
Do you know the reason why/for which he came so late?
你知道他来得这么晚的原因吗?
◆应注意关系副词和关系代词在定语从句中的不同使用。
如：
* I’ll never forget the day when I went abroad myself.
我永远忘不了我独自出国的那一天。
( when在从句中代替时间状语on the day,我们可以把这个句子分解为I’ll never forget the day.I went abroad myself on the day.)
* We’ll never forget the days that we spent together.
我们永远也不会忘记我们在一起度过的那些日子。
(that 代替the day,在句中作spent的宾语,that可以省略.该句可分解为We’ll never forget the days.We spent the days together.)
4、way 作先行词之后的定语从句
当“way”表示“方式、方法”在句中作先行词,后被一个定语从句修饰时,引导定语从句可用that ,也可用in which,或什么都不用。
如：
I don’t like the way that he laughed at me.
=I don’t like the way in which he laughed at me.
=I don’t like the way he laughed at me.
我不喜欢他用那种方式来嘲笑我。
5、time 之后的定语从句
time作先行词,前面如有序数词和last修饰时,引导定语从句不能用when,只能用that 或两者都不用.但前面如无序数词或last,常用when(有时也用that)引导定语从句。
如：
This is the last time that I shall give you a lesson.
这是我最后一次给你们上课。
The first time I saw Premier Zhou was in 1958.
我第一次见周总理是在1958年。
I don’t know the exact time when the track and field meet will take place.
我不知道田径运动会举行的确切时间。
