13. You can not have the window table, for it is reserved.
您不能用那张靠窗的餐桌，因为它已经预订出去了。
还能这样说：
The table by the window has been reseved, so you can't have it.
The window table is not available, because it has been taken by others.
14. We are a group of four.
我们有4个人。
还能这样说：
There will be four of us.
I'd like a table for 4 people.
15. How long do we have to wait?
要等多长时间?
还能这样说：
When will we get the table?
Do we need to wait for a long time to have the table?
应用解析：
wait on 服侍;
wait for 等待某人;
keep sb. waiting 使某人等候或耽搁某人(如因对方不准时)
16. I want to reserve a table for eight people.
我想预订一张8个人的餐桌。
还能这样说：
I'd like to book a table for eight people.
I want to reserve a table which is enough for eight people.
17. We can have a table reserved in a hotel.
我们可以在宾馆预订一张餐桌。
还能这样说：
We can make a reservation for a table in a hotel.
We can book a table in a hotel.