respiratory muscle

例句：

1. 1. The respiratory muscles are responsiblefor the movement of air in and outof the lungs.
   呼吸肌肉负责肺部进出空气的运动。
2. 2. During exercise, the respiratory musclesbecome stronger and more efficient.
   锻炼时，呼吸肌肉变得更强壮、更有效。
3. 3. A person withweak respiratory muscles may have difficulty breathing duringexercise or illness.
   呼吸肌肉较弱的人在运动或生病时可能会呼吸困难。