背靠背的

例句：

1. 1. She sat down on the back of the sofa.
   她坐在沙发的后背上。
2. 2. The car backed up slowly to let him pass.
   汽车慢慢地倒车以便让他通过。
3. 3. He backed away from the crowd and ran into the woods.
   他向人群后退，跑进了树林。