onprep.在 ... 之上；由 ... 支撑着；在（某一天）；关于；基于adv.穿着；向前（移动)；表示持续性adj.表示已连接、处于工作状态或使用中；发生；值班Onakan.奥纳卡(在美国；西经 99º28' 北纬 45º11')

1. The tramp carried his belongings in a pack on his back.
   那个流浪者把所有的东西捆成一包背在背上。
2. He said in a low voice, both his hands (being) on his back.
   他低声地说，他的双手放在背后。
3. The burden on his back seemed to be crushing him to the earth.
   他背上的重负似乎要把他压倒在地。
4. The traveler took out a bottle of water from the pack on his back.
   那位旅行者从他的背包中拿出了一瓶水。
5. I saw weals raise on his back.
   我看到鞭痕从他背上隆起。
6. He lay on his back and looked up at the sky.
   他仰卧著观看天空。