back up
A: 保持
B: 支持
C: 继续
D: 后退
A: 保持
B: 支持
C: 继续
D: 后退
举一反三
- He was walking ( ) along the corridor. A: back up B: back down C: back and forth D: back of
- You can' t ______your promise; all the people here are depending on you. A: back off B: back up C: back on to D: back out of
- 45（） A: up B: down C: off D: back
- 1.Whenthe control stick is_____, it_____the elevator’s trailing edge, _____the aircraft’s nose_____. A: pushed forward,lowers, pulling, up B: pulled back,lowers, pulling, up C: pulled back,raised, pushing, down D: pulled back,raised, pulling, up
- Thanksforgetting（）tome. A: Down B: Up C: Back D: Forward