【初中定语从句讲解】在初中英语学习中，定语从句是一个非常重要的语法知识点。它用于修饰名词或代词，使句子更加具体和清晰。掌握定语从句的结构和用法，有助于提高学生的阅读理解能力和写作水平。
一、定语从句的基本概念
定语从句是指在一个句子中，用来修饰主句中的某个名词或代词的从句。这个被修饰的词称为“先行词”，而引导从句的词称为“关系词”。
例句：
The book that I bought yesterday is very interesting.
（我昨天买的那本书很有趣。）
其中，“that I bought yesterday”是定语从句，修饰“book”。
二、定语从句的分类
根据关系词的不同，定语从句可以分为以下几类：
| 关系词 | 用法 | 举例 |
| that | 指人或物，作主语或宾语 | The man that is talking is my teacher. |
| which | 指物，作主语或宾语 | The car which is red is mine. |
| who / whom | 指人，who作主语，whom作宾语 | The girl who is standing there is my sister. |
| whose | 表示所属关系 | The boy whose bag is missing is crying. |
| where | 表地点 | This is the house where I was born. |
| when | 表时间 | I remember the day when we met. |
三、定语从句的使用规则
1. 关系词不能省略：当关系词在从句中作宾语时，有时可以省略，但作主语时不能省略。
- 正确：The man who is talking is my teacher.
- 正确：The man (that) I saw is my teacher.
2. 指人时可以用who或that，但在非正式语境中更常用who。
- 正确：The student who passed the exam is happy.
- 正确：The student that passed the exam is happy.
3. 指物时可以用which或that，但在非正式语境中更常用which。
- 正确：The book which I borrowed is interesting.
- 正确：The book that I borrowed is interesting.
4. 注意语序：定语从句的语序与主句一致，不倒装。
- 正确：The man who is sitting next to me is my friend.
- 错误：The man sitting next to me who is my friend.
四、常见错误与注意事项
| 常见错误 | 正确表达 | 解释 |
| The girl which is beautiful is my classmate. | The girl who is beautiful is my classmate. | 指人用who，不用which。 |
| The house where I live is big. | The house in which I live is big. | 当表示“在……里面”时，可用where或in which。 |
| The time when I met her was unforgettable. | The time at which I met her was unforgettable. | 表示时间时，也可用at which，但更常用when。 |
五、总结
定语从句是初中英语的重要语法内容，掌握其结构和用法对提升语言表达能力有重要意义。通过理解关系词的作用、正确使用语序以及避免常见错误，学生可以在实际应用中更加自如地运用定语从句。
| 知识点 | 内容 |
| 定义 | 修饰名词或代词的从句 |
| 关系词 | that, which, who, whom, whose, where, when |
| 用法 | 指人用who/that，指物用which/that |
| 注意事项 | 不可随意省略关系词，注意语序和搭配 |
通过不断练习和积累，定语从句的学习将变得更加轻松和有效。
