英语中的句子可以根据其结构分为简单句和复合句。

简单句

定义：简单句只包含一个主谓结构，可以有一个或多个宾语、定语、状语等修饰成分，但不含从句。

例句：

I like English.

The man cooks.

They are playing baseball in the garden.

She sat down beside me.

复合句

定义：复合句由两个或两个以上的简单句通过连词连接而成。连词可以是并列连词（如and, or, but）或从属连词（如if, because, although等）。

例句：

The students I teach have made great grades in the past few weeks.

The boy who I know is his brother.

You jump, I jump. （from Titanic）

What he wants to tell us is not clear.

Whether there is life on the moon is an interesting question.

I think english is very important.

I like music that has great lyrics.

建议

在学习和使用英语句子时，理解简单句和复合句的基本结构是非常重要的，这有助于更好地表达思想和理解复杂的句子结构。

通过多读多写，可以逐渐掌握不同类型句子的构造和用法，从而提高英语写作和口语能力。