ㄅㄧㄥㄉㄨㄥˋbīngdòngㄙㄢsānˇchǐㄈㄟfēiˊˋzhīㄏㄢˊhán

冰冻三尺,非一日之寒
bīngdòng sān chǐ, fēi yī rì zhī hánㄅㄧㄥ ㄉㄨㄥˋ ㄙㄢ ㄔˇ,ㄈㄟ ㄧ ㄖˋ ㄓ ㄏㄢˊ
  1. 不可能一天形成比喻現在事情狀況漸漸積累逐步形成暗示現有情況不易消除 此事其來有自冰凍三尺,非一日之寒」。

three feet of ice does not form in a single day (idiom)​; Rome wasn't built in a day