在英语语法中，定语从句是一种非常重要的句式结构，它通过修饰名词或代词来提供更多的信息。定语从句通常由关系代词（如who, whom, whose, which, that）或关系副词（如where, when, why）引导。根据不同的引导词和使用场景，我们可以将定语从句大致分为以下八种类型：
1. 关系代词型 - who/whom
这种类型的定语从句用来修饰人，其中“who”用于指代主格，“whom”用于宾格。例如：
- The man who is speaking is my teacher.
- The student whom I met yesterday is very friendly.
2. 关系代词型 - whose
“whose”表示所属关系，可以修饰人也可以修饰物。例如：
- The book whose cover is red belongs to me.
- The girl whose father works abroad lives next door.
3. 关系代词型 - which
“which”主要用来修饰事物，并且可以在非限定性定语从句中使用。例如：
- This is the house which I lived in last year.
- She bought a car, which was very expensive.
4. 关系代词型 - that
“that”既可以修饰人也可以修饰事物，在限定性定语从句中较为常见。例如：
- The boy that answered the question is my brother.
- The movie that we watched last night was fantastic.
5. 关系副词型 - where
“where”用来修饰地点，在定语从句中充当状语。例如：
- This is the park where I often play basketball.
- The restaurant where we had dinner is very popular.
6. 关系副词型 - when
“when”用来修饰时间，在定语从句中充当状语。例如：
- Do you remember the day when we first met?
- Last summer, when I traveled to Beijing, it rained every day.
7. 关系副词型 - why
“why”用来修饰原因，在定语从句中充当状语。例如：
- That's the reason why he didn't come to the party.
- There must be a reason why she left so early.
8. 不含关系词的定语从句
有些定语从句可能省略了关系词，尤其是在“that”引导的情况下。例如：
- The book (that) I borrowed from the library is very interesting.
- The city (that) we visited last week is beautiful.
以上就是定语从句的八种基本类型。掌握这些不同类型有助于更准确地理解和运用定语从句，从而提高英语写作和口语表达的能力。希望本文能帮助大家更好地理解这一语法知识点！
