一、名词性从句
主语从句 - 例句：What he said is true.
- 句子成分：
- 主语：What he said
- 谓语：is
- 补语：true
宾语从句
- 例句：I know that he is a doctor.
- 句子成分：
- 主语：I
- 谓语：know
- 宾语：that he is a doctor
表语从句
- 例句：This problem is difficult to solve.
- 句子成分：
- 主语：This problem
- 系动词：is
- 表语：difficult to solve
同位语从句
- 例句：The reason why he was late is that he forgot his wallet.
- 句子成分：
- 主语：The reason
- 谓语：is
- 表语：that he forgot his wallet
二、定语从句
例句：The book which/that I borrowed from the library is very interesting.
句子成分：
主句：The book is very interesting
定语从句：which/that I borrowed from the library
关系词：which/that（指代book）
三、状语从句
时间状语从句
- 例句：When you call me, I will be at home.
- 句子成分：
- 主句：I will be at home
- 时间状语从句：When you call me
- 连接词：When
原因状语从句
- 例句：Because it rained, the match was canceled.
- 句子成分：
- 主句：The match was canceled
- 原因状语从句：Because it rained
- 连接词：Because
条件状语从句
- 例句：If it snows tomorrow, we will cancel the trip.
- 句子成分：
- 主句：We will cancel the trip
- 条件状语从句：If it snows tomorrow
- 连接词：If
四、其他类型从句
结果状语从句： He was so angry that he couldn't speak. 连接词：so...that... 让步状语从句
连接词：Although
总结
从句是英语语法中功能强大的成分，通过不同类型（名词性、定语、状语、同位语）修饰句子。掌握各类从句的引导词（如that、which、when、because等）及句式结构，有助于提升英语表达的准确性和丰富性。
