我们注意到街对面有一栋空建筑。

We noticed a ___vacant building across the street.

隔壁房间目前是空着的。

The room next to ours is ___vacant at the moment.

你看，我们有很多空房间，所以你不会造成任何麻烦。

You see, we have plenty of ___vacant rooms so you would not cause any trouble.