different的名词是什么

　　It's the difference between a pass and a fail.

　　这是及格和不及格的区别。

　　It took a practised eye to spot the difference.

　　只有内行人才能看出其中的差异。

　　Can you spot the difference between these two pictures?

　　你能不能看出这两幅画有什么不同？