jump the gun
过早地行动；做事冲动
口语·形容冲动或过早行动
英文释义
to start doing something too soon, before it is appropriate or before the necessary preparations have been made
例句
He jumped the gun and announced the news before it was official.
典故来源
源自田径比赛，发令枪响前起跑即犯规，比喻过早行动。