at the drop of a dime
立刻或毫不犹豫地做某事
口语·表示立即行动或毫不犹豫
英文释义
to do something immediately or without hesitation
例句
She would help her friend at the drop of a dime, no questions asked.
典故来源
源自美国20世纪中期，投币电话中一枚10美分硬币（dime）掉落即可立即通话，比喻行动迅速毫不犹豫。