on the fly
即兴进行的；不经准备的
口语·描述即兴或快速处理
英文释义
doing something quickly or on the spot, without much preparation or planning
例句
We didn't have time to plan the party; we just organized it on the fly.
典故来源
源自棒球术语，指接住飞行的球，后引申为在过程中快速应对或即兴完成。