名词

名词短语

限定词+修饰词+主题词=名词短语，比如 a good boy。

代词

  1. 人称代词
  2. 指示代词
  3. 不定代词
  4. 疑问代词

数字

基数词

  1. 整数
  2. 小数
  3. 分数
  4. 百分数

序数词

不定式

To learn English well is very important. It is very important to learn English well.

动名词

Smoking is bad.

句子

That you are a pig is a fact. It is a fact that you are a pig.