Don't arrive late for class.Don't eat in the classrooms.

问题描述:

Don't arrive late for class.Don't eat in the classrooms.
class,classroom,同为名词,为什么class后面不加S,classroom加S?

Don't arrive late for class.Don't eat in the classrooms.
上课别迟到,别在教室吃东西.
class是课程,上课,强调事件
classroom,教室.强调地方,教室那个房间,