I'm sorry, but I'm quite a stranger around here.

对不起，我对这里也很陌生。

I'm sorry,I'm not sure. You can ask someone else.

很抱歉，我也拿不准。你可以问问别人。

I'm sorry,this is my first time here,too.

对不起，我也是初来此地。

I'm a stranger here myself, and I do not know much about this place.

我也是外地人，对这里也不熟悉。

I suggest you ask the cop over there.

我建议你去问那边的警察。