文/普通的马儿
今天我们从三个简单句开始：
I graduated from this school. And I met my first girlfriend in this school. But I broke up with my first girlfriend.我从这个学校毕业。我在这个学校遇到了我的初恋女友。但是我跟我初恋女友分手了。
这里this school出现2次，my first girlfriend出现2次,显得啰嗦。能不能只说一遍，简洁点？当然可以啦！
I graduated from this school in which I met my first girlfriend with whom I broke up.
貌似不简单的样子啊！这里which指物，whom指人（宾格）。
我们先看which的从句：
I graduated from this school in which I met my first girlfriend .
它是由 I graduated from this school. And I met my first girlfriend in this school.组成。第二句也可以写成In this school,I met my first girlfriend.
两句加起来： I graduated from this school, in this school,I met my first girlfriend.
用which替换第二个his school:
I graduated from this school in which I met my first girlfriend.
再看whom的从句
I met my first girlfriend with whom I broke up.
它是由I met my first girlfriend in this school. But I broke up with my first girlfriend.组成。
用whom替换第二个my first girlfriend：
I met my first girlfriend with whom I broke up in this school.
最后，I graduated from this school in which I met my first girlfriend.与I met my first girlfriend with whom I broke up in this school.整合为：
I graduated from this school in which I met my first girlfriend with whom I broke up.
练习1.将两个简单句整合成一个从句
This is an old computer. It works much slower.这是一台老式电脑。它工作起来速度较慢。
an old computer是物体，所以用which。
This is an old computer which works much slower.这是一台工作速度较慢的老电脑。
练习2.
I have many friends. I am going to send postcards to them.我有很多朋友。我打算寄贺卡给他们。
指人（宾格）用whom
I have many friends to whom I am going to send postcards.我有很多打算寄贺卡的朋友。
以上所讲从句是定语从句。
定语从句在句中的作用相当于形容词，用来修饰名词、代词或整个主句。
引导定语从句的词被称为关系词。分为关系代词和关系副词。常用的关系代词有who,whom,whose,that,which,as等。
who,whom指人
whose一般指人，有时也指物
that指人或物
which一般指物
as指人或物，也可指整个句子。
常用的关系副词有where,when,why等。
where表示地点
when表示时间
why表示原因
In this accident,the number of people who died reached as many as 25.我这次事故中，死亡人数多达25人。
You're the only one whose advice he might listen to.只有你的建议他可能会听。
The train ran over and killed a boy and his dog that were just crossing the track.火车飞奔过去，轧死了正在穿过轨道的孩子和他的狗。
The picture that we are looking at was drawn by a fifteen years old student.我们将看到这幅画是一个十五岁的学生画的。
The explorer took only such men and things as he really needed into the jungle.这个探险者进入丛林时，仅带了一些他认为确实需要的人和物品。
Let's meet at the same place as we did yesterday.咱们在昨天见面的地方见面吧。
As everybody knows,Shakespeare is famous writer.总所周知，莎士比亚是一位著名的作家。
Potato can be grown in places where it is too cold to grow rice.有些太冷不能种水稻的地方，可以种马铃薯。
I shall never forget the days when we worked on the farm.我永远也不会忘记，我们在农场劳动的那些日子。
Can you tell me the reason why the car broke down?你能告诉我车子坏了的原因吗？
更多从句语法知识，请参考《星火英语语法全解》
作者：普通的马儿 小学英语教师，喜欢研究各种学习方法，喜欢阅读小说，总想写点什么的待产孕妈。
计划每日写一篇文章，每日复习新学英语单词200个，每周学一首英文歌。
