difference是可数名词吗?

difference可数。
difference表示“差别，不同”的时候既可做可数也可做不可数名词，表示“差额”时不可数。
相关例句：He was studying the complex similarities and differences between humans and animals差别不止一处，因此用了复数形式。
相关例句：I can never tell the difference between the twins这里指的不是具体的某处差别，而是指总体、概括、抽象意义上的差异，因此不可数。

可数，也可以不可数：
difference 表示"差异,差别",可数:
There are many differences between living in a city and living in the country.生活在城市和生活在乡村有许多不同之处.
difference 表示"差额,差数",不可数:
The difference between 5 and 11 is 6.十一和五的差是六.
Flowers make no/a lot of difference to a room. 一个房间里有没有鲜花没有/有很大差别.
It doesn't make much/any/the least difference to me what you do .你干什么对我都没有多大/任何/丝毫关系.
When you're learning to drive, having a good teacher makes all the difference.初学驾驶如有好的老师指导,差别很大.
difference 表示"不和,分歧",可数:
They've settled their differences and are friends again.他们已消除芥蒂,重归于好.