化學需氧量 huà xué xū yǎng liàng

DEFINITIONS

  1. chemical oxygen demand (an environmental indicator)

CHARACTERS

化 huà
HSK 3
change, convert, reform; -ize
學 xué learning, knowledge; school
需 xū
HSK 3
need, require, must
氧 yǎng
HSK 6
oxygen
量 liàng
HSK 4
measure, quantity, capacity