Do you have reservations?
您订位了吗？
reservation 预定，预约 Room reservation 订房

Is this for here or to go?
在这里吃还是带走？
Can I order take-out here?
我可以叫菜带走吗？
take-out 带走的菜

Would you like a table in the smoking or nonsmoking section?
您要在吸烟区还是非吸烟区？

You would better not jump the line?
你最好不要插队。
jump the line 插队

What is today's specialty?
今天的特色菜是什么？
Specialty: 特色菜

I am afraid we will have to cancel the order.
恐怕那道菜我们不要了。
cancel the order 不点了

What would you recommend?
你们推荐什么？
What do you think I should order?
What is your suggestion?
What do you suggest to order?

I'll treat you tonight.
今天晚上我请客。
No, let's go Dutch.
别了，我们AA制吧。
go Dutch: AA制，也可以说 split the bill。

还要别的什么吗？
And what to follow?
Won't you have more?
Anything else you want?
Is there anything else that you'd like?