It's forbidden to smoke here

禁止吸烟

I can't help smoking.

我忍不住要抽烟了。

I advise you not to do it here. I don't think it's allowed.

我建议你别在这里抽烟。这里不允许吸烟。

Well, I can't care for so much.

可是，我管不了那么多了。

Excuse me, sir. It's forbidden to smoke here. Would you please put your cigarette out?

打扰一下，先生。这里禁止吸烟，能不能把烟掐灭呢？

Oh, I am sorry, sir.

哦，非常抱欺，先生。