My last class is over at 3:30.

我最后一节课是在三点半结束。

Class is over. Let's play balls.

下课咯，去玩球吧。

The class is over. You can go home now.

下课了，你们可以回家了。

Class is over.

下课。

Class is over. Let's take ten minutes' break.

下课了。让我们休息十分钟。