不分昼夜 bù fēn zhòu yè

DEFINITIONS

  1. day and night
  2. round-the-clock

CHARACTERS

不 bù
HSK 1
no, not; un-; negative prefix
分 fēn
HSK 1
divide; small unit of time etc.
昼 zhòu
HSK 6
daytime, daylight
夜 yè
HSK 5
night, dark; in night; by night