Difference，是different的名词形式，在考试中常出现不同意义下单复数的差别
(1) 表示差别，差异；分歧，不和的时候，可数
There are many differences between living in the city and living in the countryside.
They have many differences in the agreement.
(2) 表示差额时，不可数 名词
The difference between 5 and 8 is 3.
