【初中定语从句专项讲解与练习.】在英语学习中，定语从句是一个非常重要的语法知识点，尤其在初中阶段的英语教学中占据着重要位置。掌握好定语从句不仅有助于提高阅读理解能力，还能在写作中让句子更加丰富和准确。本文将对初中阶段常见的定语从句进行详细讲解，并附上相应的练习题，帮助同学们更好地理解和运用。
一、什么是定语从句？
定语从句是指在句子中起定语作用的从句，用来修饰名词或代词。它通常由关系代词（如 who, whom, whose, which, that）或关系副词（如 when, where, why）引导，放在被修饰的词之后。
例如：
- The book that is on the table is mine.
（那本在桌子上的书是我的。）
这里的 “that is on the table” 就是定语从句，修饰 “the book”。
二、常见关系代词与关系副词
| 关系词 | 用法说明 | 例句 |
|--------|----------|------|
| who| 指人，作主语或宾语 | The girl who is talking to Tom is my sister. |
| whom | 指人，作宾语 | The man whom you met yesterday is a teacher. |
| whose| 表示所属关系 | The boy whose bag was stolen is crying. |
| which| 指物，作主语或宾语 | The car which is red is mine. |
| that | 指人或物，作主语或宾语 | The man that is standing there is my father. |
| when | 表时间，作状语 | I still remember the day when we met. |
| where| 表地点，作状语 | This is the house where I was born. |
| why| 表原因，作状语 | That’s the reason why he left. |
> 注意：在非正式场合中，“that”常可代替“which”或“whom”，但在正式写作中应根据语境选择合适的引导词。
三、定语从句的使用规则
1. 关系代词不能省略：当关系代词在从句中作主语时，不能省略。
- ✅ The student who is sitting next to me is from Beijing.
- ❌ The student is sitting next to me is from Beijing.
2. 关系代词作宾语时可以省略：当关系代词在从句中作宾语时，可以省略。
- ✅ The man (that) I saw yesterday is my uncle.
- ✅ The book (which) she gave me is very interesting.
3. 注意先行词的单复数：关系代词要与先行词保持一致。
- ✅ The girls who are in the classroom are my classmates.
- ✅ The girl who is in the classroom is my classmate.
四、定语从句的常见错误
1. 混淆 who 和 whom
- 错误：The person who you met is my friend.
- 正确：The person whom you met is my friend.
（“whom”在从句中作宾语，但口语中常用“who”）
2. 关系代词与先行词不一致
- 错误：The books that are on the table are mine.
- 正确：The book that is on the table is mine.
（“book”是单数，所以用“that is”）
3. 遗漏关系词
- 错误：I don’t know he is.
- 正确：I don’t know who he is.
（缺少关系代词“who”）
五、练习题
一、选择正确的引导词填空：
1. The man ______ is talking to the teacher is my father.
A. who B. which C. whom D. when
2. The girl ______ won the prize is my classmate.
A. who B. which C. whom D. where
3. The house ______ I was born is very old.
A. who B. which C. where D. why
4. The reason ______ he didn’t come is unknown.
A. who B. which C. why D. when
5. The book ______ I borrowed is very interesting.
A. who B. which C. when D. where
二、改写句子（用定语从句）：
1. This is the girl. She helped me with my homework.
→ This is the girl who helped me with my homework.
2. The city is famous. It is located in the south of China.
→ The city which is located in the south of China is famous.
3. The problem is difficult. We can’t solve it.
→ The problem that we can’t solve is difficult.
六、总结
定语从句是初中英语语法中的重点内容，掌握其结构和用法对于提升语言表达能力至关重要。通过不断练习和积累，同学们可以在实际应用中更加自如地使用定语从句，增强英语综合能力。
希望本文能帮助大家更好地理解和掌握定语从句的相关知识，为今后的英语学习打下坚实的基础。
