复合句的种类
英语的复合句一般分为三大类型：名词性从句、形容词性从句和副词性从句。
名词性从句
在整个复合句中起名词作用，充当主语、宾语、表语和同位语等的各种从句，统称为名词性从句。名词性从句主要有以下几种：
1. that引导的从句e.g. It is reported that one third of Guangzhou citizens plan to buy a private car.
2. whether/if引导的从句e.g. Whether motorcycles should be banned in Guangzhou has become an issue of controversy。
3. how/why/when/where引导的从句e.g. This essay aims to explore why so many white collar workers suffer from insomnia.
4. who/whom/whose/what/which引导的从句e.g. Who should be responsible for the environmental degradation is still unknown。
形容词性从句
具有形容词功能，在复合句中做定语的从句被称之为形容词性从句或定语从句。被修饰的名词、词组或代词被称为先行词。形容词性从句分为两种类型：
由关系代词who, whom, whose, that, which, as引导的从句。例如： People who are strongly against human cloning claim that it is immoral and unethical.
由关系副词when, where, why引导的从句。例如： I would like to analyze the reasons why a growing number of teenagers are addicted to gambling。
