In airbreathing vertebrates, one of two organs of breathing, in which the blood gives up water and carbon dioxide and receives oxygen.

【解】肺；肺脏。

Breathing spaces, such as small parks that might be placed in overpopulated or traffic-congested areas.

市肺(都市中可呼吸新鲜空气的地方，如在人口稠密和交通拥塞的地区之中设置的小公园)。