black mud

短语

词形变化

black muds 复数 black muds

释义与例句

n.
  1. 1.

    Used other than figuratively or idiomatically: see black, mud.

    可数 不可数
  2. 2.

    Reduced mud found below the surface of sediments in lakes and rivers, the blackness of which is caused by the occurrence of metal sulphides.

    可数 不可数