Musculus flexor digitorum longus

例句：

1. 1.The muscles in the arms are working hard to lift the heavy box.
   手臂上的肌肉正在努力举起这个重箱子。
2. 2. Muscles are essential for our daily activities and physical fitness.
   肌肉是我们日常活动和保持身体健康所必需的。
3. 3.The doctor advised him to exercise regularly to maintain his muscle strength.
   医生建议他定期锻炼以保持肌肉力量。