凹陷

Said in one Chinese podcast line.

• 基本上就是凸起和凹陷的变化

  It basically refers to the changes between protrusions and depressions.

  

  美国万花筒 - 美国之音美国万花筒:国际社会旅行警告惹怒特朗普；联合国:少吃肉缓解全球变暖；著名男高音多明戈被指性骚扰 - 8月 17日,2019年

The shows belong to their publishers, and each line plays from the publisher’s own file. Translations are machine-made. Chinese books and courses on Amazon (affiliate link).