颈背

例句：

1. 1. He sat on the couch, his neck and back straight.
   他坐在沙发上，脖子和背部挺直。
2. 2. She stretched her neck and back to relieve some tension.
   她伸展脖子和背部以缓解一些紧张。
3. 3. The doctor advised him to exercise regularly to maintain good posture.
   医生建议他定期锻炼以保持良好的姿势。