lung being reservoir of phlegm

例句：

1. 1. The lungs are responsible for breathing.
   肺部负责呼吸。
2. 2. He had a lung infection and needed to be hospitalized.
   他得了肺部感染，需要住院治疗。
3. 3.She was coughing up blood from her lungs.
   她的肺部咳出了血。