定语从句(Relative Clauses)是一种修饰名词或代词的从句,在句子中充当形容词的角色。定语从句用来给出更多关于前面名词或代词的信息,通常用以限定或描述这个名词或代词,使句子更加详细和清晰。定语从句的引导词通常是关系代词(例如:who, whom, whose, which, that)或关系副词(例如:when, where, why)。
### 定语从句的基本结构:
1. **关系代词引导的定语从句:**
- The person **who** is standing over there is my friend.
- I met the girl **that** you were talking about.
2. **关系副词引导的定语从句:**
- This is the place **where** I was born.
- He explained the reason **why** he was late.
### 定语从句的用法:
1. **限定性定语从句(Defining Relative Clauses):** 这种定语从句给出了对前面名词或代词的限定性信息,如果去掉定语从句,主句的意思就不完整。
- The book **that** I am reading is very interesting.
- The woman **who** lives next door is a doctor.
2. **非限定性定语从句(Non-defining Relative Clauses):** 这种定语从句提供了额外的信息,但不是必需的,即使去掉定语从句,主句的意思仍然完整。
- My brother, **who** lives in London, is coming to visit us.
- The Eiffel Tower, **which** is located in Paris, is a famous landmark.
在写定语从句时,需要注意引导词的选择、定语从句的位置以及与先行词的一致性,以确保句子的结构和意思都正确。