拿著刀子就割东西。语本《左传・襄公三十一年》：“今吾子爱人则以政，犹未能操刀而使割也。”比喻做事须即时行动。《汉・贾谊・上疏陈政事》：“黄帝曰：『日中必蔧，操刀必割。』”
英语 Having got hold of a knife,one must cut--not to lose an opportunity when there is one
