1. sit near the window 靠窗坐
The waiter inquired whether we would like to sit near the window.
2. be seated 就坐
If you find a waiter you like, always ask to be seated in his or her section.
3. It's my treat. 我请客。
It's my treat. what would you like to drink?
4. busy 热闹的，繁忙的
The next 12 months will be busy.
5. fast food restaurant 快餐馆
While you may not have recognized it was happening, the last time you ordered from a fast food restaurant there is a good chance you experienced cross-selling.
6. ... will be fine ……就好，……就行了
I'd tell him to relax and everything will be fine.