once in a blue moon

短语

千载难逢地

发音

AU /wʌns ɪn ə bluː muːn/

释义与例句

adv.
  1. 1.

    Very rarely; very infrequently.

    千载难逢

    十年唔逢一闰

    习语

词源

See blue moon. First use appears c. 1833. See citation below.

来源：wiktionary