They must have gotten to the top of the mountain by now. They_____ before the sun rose. A...
| B |
| 试题分析： A. settled down 定居下来，安静下来，B. set out出发，动身，C. took off脱下，起飞，D. turned up[出 现，露面，句意：现在他们一定到了山顶，他们在太阳升起前出发的。所以选B。 |
| B |
| 试题分析： A. settled down 定居下来，安静下来，B. set out出发，动身，C. took off脱下，起飞，D. turned up[出 现，露面，句意：现在他们一定到了山顶，他们在太阳升起前出发的。所以选B。 |