1. We will have to finish it at this time tomorrow. at=在

2. The firemen arrived soon and got the fire under control. under=在下 (在control下)

3.You can wash there spots off with a brush

off=下来

4. The printing office buys paper in quantities

5.He is ill, so I'll go there in place of him

6. Rain came down just before daybreak

down=下来

7. I have a poor sense of direction

不需修改

8. To our surprise, he failed the exam

To=给

9. Don't laugh at a person who is in trouble

at=向 (再这个句子当中这么用)

10. A person who put up a good plan will be rewarded.

up=上