Let's go to the waiting room and take a rest.

我们到候车室去休息一下吧。

Let's sit down and take a rest.

我们坐下来，歇歇脚吧。

You take a rest. Let me do it.

你歇歇，让我来吧。

He simply refused to take a rest.

他就不肯歇一歇。

Let's sit down and take a rest for a while.

我们坐下来，少憩片刻吧。