英语中什么是 复杂句，复合句， 简单句？ 能给我举例一下吗？

     复合句是两个或两个以上的简单句组成，每个简单句都有主谓，句子句子之间由连词连成；复合句分为并列复合句（也称并列句）和主从或从属复合句也称复杂句）。

如：What were you doing when your mother arrived home?
He said that he was late for school yesterday.

    复杂句也称为从句、主从复合句，由一个主句和一个或一个以上的从句构成，用代词、副词、连词把一个简单句作为另外一个简单句的从属成分的句子；某个句子成分直接由从属分句表示，那么这种句子便不是简单句而是复杂句。

如：The students would have made better grades if they had studied hard.

简单句就是只含有一个主谓结构并且句子各成分都只由单词或短语构成的独立句子或分句。在简单句中主语和谓语是句子的主干，是句子的核心。

如：I like English very much. 

     You are a good student.

英语句子分为：简单句，并列句和复合句
简单句只包含一个主语，谓语，
如：I like English very much. You are a good student.
并列句由and, but, so, or等连接词连接的两个以上的句子
如：Hurry up! Oh you will be late.
He like dancing but he prefers swimming.
复合句：至少两个以上的句子，又分为：宾语从句，状语从句，定语从句等
如：What were you doing when your mother arrived home?
He said that he was late for school yesterday.