脊背

例句：

1. 1. The scientist carefully examined the vertebrae of the animal's back.
   科学家仔细检查了动物背部的椎骨。
2. 2. She sat on her back with her legs crossed.
   她交叉着腿坐在背上。
3. 3. He leaned against the wall, his back to the door.
   他靠在墙上，背对着门。