cavities/ˈkæv.ə.t̬i/名词空隙；洞；腔The gold was hidden in a secret cavity.金子藏在一个隐秘的洞穴里。（牙齿上的）龋洞，蛀牙洞（身体内的）腔the upper nasal cavity鼻腔上部想跟读，去练习
