She called just as we were sitting down to eat.我们刚要坐下吃饭，她就打来了电话。

Come on in and sit down. [=have a seat]进来坐下吧。

Please sit down and be quiet.请就座，并保持安静。

We need to sit down and figure this problem out. [=we need to give our attention to figuring this problem out]我们需要认真弄明白这个问题。

She made sure everyone was sitting down before she began.她先确认每个人都坐下来了才开始。

I have some shocking news. Are you sitting down?我有惊人的消息。你们坐好了吗？

He sat the child down.他让孩子坐好了。

You need to sit him down and have a talk with him.你需要让他坐下来和他谈谈。

She sat herself down on the couch.她坐到了沙发上。