若要在兩個相等數量的事物上做比較，我們會套用這個公式：
as + 表明分量的形容詞 +（名詞）+ as
至於要使用的分量形容詞為何，取決於比較的名詞是可數還是不可數。
可數名詞
若比較的名詞是可數的，則用 as many 以及 as few。要注意，當前面的句子已表明比較的事物為何，就可以不重複，下面最後一個例句針對此情況來示範。
舉例
- They have as many children as we do.
- We have as many customers as they do.
- Tom has as few books as Jane.
- There are as few houses in his village as in mine.
- You know as many people as I do.
- I have visited the States as many times as he has.
- I have three brothers. That's as many as you have.（從第一個句子可看出要比較的事物是「brothers」）
不可數名詞
若比較的名詞是不可數的，則用 as much 以及 as little。要注意，當前面的句子已表明比較的事物為何，就可以不重複，下面最後一個例句針對此情況來示範。
舉例
- John eats as much food as Peter.
- Jim has as little patience as Sam.
- You've heard as much news as I have.
- He's had as much success as his brother has.
- They've got as little water as we have.
- I'm not hungry. I've had as much as I want.（由第一個句子可知，後面要比較的事物是「food」）