lock the stable door after the horse has bolted
亡羊補牢
口語·批評遲來的預防措施
英文釋義
to take precautions or preventive measures after damage has already been done
例句
Apologizing now is like locking the stable door after the horse has bolted.
典故來源
源自16世紀英國諺語,馬跑后才鎖門,比喻事后補救為時已晚。