一文掌握定语从句的核心语法与表达技巧
一、定义与功能说明
定语从句（Relative Clause）是用于修饰前面名词（先行词）的一类从句，通常由关系代词或关系副词引导，功能等同于形容词。通过使用定语从句，我们可以将两个简单句合并成一个表达更完整的复合句，从而提升语言表达的条理性和准确性。
二、关系词分类与句法位置
1. 关系代词
| 词 | 指代对象 | 在从句中作用 | 示例 |
|---|---|---|---|
| who | 人 | 主语 | The man who helped me is a teacher. |
| whom | 人 | 宾语 | The person whom I met was kind. |
| whose | 人或物 | 定语 | A student whose name is Jack won the prize. |
| which | 物 | 主语/宾语 | The house which stands there is old. |
| that | 人或物 | 主语/宾语 | The story that you told is interesting. |
2. 关系副词
| 词 | 指代内容 | 示例 |
|---|---|---|
| when | 时间 | I remember the time when we met. |
| where | 地点 | This is the city where I was born. |
| why | 原因 | That’s the reason why he left early. |
三、限定性与非限定性定语从句的区分
✅ 限定性定语从句
必要成分，不可省略，句中不加逗号：
- Students who work hard will succeed.
- I like books that inspire me.
✅ 非限定性定语从句
补充说明，句中使用逗号隔开，不可使用 that：
- My uncle, who lives in Canada, is visiting us next week.
- This novel, which was published in 1990, is still popular.
四、语法要点提醒
- 非限定性定语从句不可用 that；
- 注意先行词与从句谓语的一致；
- whom 常被口语中省略为 who 或直接省略；
- 定语从句中缺少的成分通常由关系词补位。
五、句型合并与例句演示
将以下句子合并成一个含定语从句的复合句：
- The boy is my cousin. He is wearing a red cap.
✅ The boy who is wearing a red cap is my cousin. - I visited a museum. It was founded in 1920.
✅ I visited the museum which was founded in 1920.
六、写作范文片段
In today’s fast-changing world, students who can adapt to new environments are more likely to succeed. The ability to communicate with people who come from different cultures has become increasingly important. This is the reason why schools emphasize international exchange programs.
此段落中自然嵌入多个定语从句，有效提升了句式层次和表达深度，是高分写作的重要技巧。
七、学习建议
- 针对关系词分类做专项练习；
- 多做句子合并训练，提升结构运用能力；
- 仿写范文，掌握书面表达中定语从句的常用模板。
如果你希望系统掌握像定语从句这样的重要语法结构，推荐使用我们的 “李校来啦英语智能训练系统”。该系统通过结构拆解、例句替换、句型重构等模块，帮助你逐步建立英语句式的逻辑体系，是提升语法应用能力的高效工具。