In a “比”sentence with an adjectival predicate, the complement of quantity (a numeral- measure word phrase) can be used after the main element of the predicate to express specific differences between two things or persons.
A + Numeral—measure word phrase
Subject
Predicate
“比”
N/P
(the object of comparison)
A
(the aspect of comparison)
Numeral--measure word phrase
(the result of comparison)
这件衣服
这本书
这件
我们系
比
比
比
比
那件衣服
那本书
那件
他们系
大
贵
长
多
一号。
20块钱。
两公分。
90个学生。
The word “一点儿” is used to indicate a slight difference between two things or persons, while “多了”is used to indicate that the difference is great. For example: 这件衣服比那件贵一点儿。 这个电脑比那个新多了。 The question form for this type of sentence is “A + 多少”. For example: 你们系比他们系多多少人? 这件衣服比那件贵多少(钱)?