clean up|cleaning up

我们离开前必须清理干净。

We have to ___clean ___up before we leave.

在我们住宿期间，没有人来清理房间，而且员工不太友好。

During our accommodation there, nobody came to ___clean ___up the room and the staff was not very friendly.

他们正在开发清理污染河流的工艺。

They are developing processes to ___clean ___up polluted rivers.

我也可以通过分发传单来帮助，传单上包含如何开始清理环境的信息。

I can also help by distributing leaflets which contain information on how to start ___cleaning ___up the environment.