铁树开花 tiě shù kāi huā

DEFINITIONS

  1. lit. the iron tree blooms (idiom)
  2. a highly improbable or extremely rare occurrence

CHARACTERS

铁 tiě
HSK 3
iron; strong, solid, firm
树 shù
HSK 3
tree; plant; set up, establish
开 kāi
HSK 1
open; initiate, begin, start
花 huā
HSK 3
flower; blossoms