【定语从句例句】在英语学习中，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。定语从句通常由关系代词（如 who, whom, whose, which, that）或关系副词（如 when, where, why）引导。以下是对定语从句的总结，并附上一些常见例句供参考。
一、定语从句基本结构
定语从句的基本结构为：
先行词 + 关系词 + 从句
- 先行词：被修饰的名词或代词。
- 关系词：引导从句并充当从句中的成分（主语、宾语、定语等）。
- 从句：对先行词进行说明或限制的句子。
二、定语从句分类与用法
| 分类 | 关系词 | 用法说明 | 例句 |
| 限制性定语从句 | that, which, who, whom, whose | 修饰先行词，不能省略，否则句意不完整 | The book that I bought is very interesting. |
| 非限制性定语从句 | which, who, whom, whose | 对先行词作补充说明，可省略，用逗号隔开 | My brother, who lives in Beijing, is a doctor. |
| 以 that 引导 | that | 既可指人又可指物，常用于正式文体 | The man that you met yesterday is my teacher. |
| 以 which 引导 | which | 仅指物，常用于非限制性从句 | The house which we visited last week is beautiful. |
| 以 who/whom 引导 | who, whom | 指人，who 作主语，whom 作宾语 | The girl who is singing is my sister. |
| 以 whose 引导 | whose | 表示所属关系，指人或物 | The student whose essay was praised is from Class 2. |
| 以 when/where/why 引导 | when, where, why | 作状语，修饰时间、地点或原因 | I remember the day when we first met. |
三、定语从句常用例句
| 句子 | 解析 |
| The man who is standing there is my father. | who 引导的定语从句，修饰 “the man”，作主语 |
| The car which she bought last month is very fast. | which 引导的非限制性定语从句，修饰 “the car” |
| The teacher whom I admire most is Mr. Li. | whom 引导的定语从句，作宾语 |
| The reason why he left is unknown. | why 引导的定语从句，修饰 “the reason” |
| The house where we lived is now a museum. | where 引导的定语从句，修饰 “the house” |
四、定语从句注意事项
1. 关系词不能省略：当关系词在从句中作宾语时，若放在句首，不能省略。例如：
- 正确：The book that I read is interesting.
- 错误：The book I read is interesting.（口语中有时可以省略，但书面语中建议保留）
2. 注意指代对象：关系词要根据先行词是人还是物来选择。例如：
- 指人：who, whom, whose
- 指物：which, that, whose
- 指时间：when
- 指地点：where
- 指原因：why
3. 非限制性定语从句：使用逗号隔开，不能用 that 引导，只能用 which、who、whom、whose。
通过以上总结与例句，可以更清晰地掌握定语从句的用法和结构。在实际写作和阅读中，多加练习有助于提高语言表达的准确性和丰富性。
