after class 下课后，课下
class is over 下课了，放学了
意思差不多，都含有“下课，放学”的意思。
eg. Class is over. The students walk the classroom 下课了，同学们走出了教室。
Class is over. Good-bye, class. 下课了。同学们再见。
When the class is over, they take other books from lockers, then move to another classroom.
这节课结束后，他们从储物柜里取出其他的课本再到另外的教室去上课。
Come to my office after class.下课后到我的办公室来。
Lily always does her homework after class.莉莉总是放学就做作业。