close, lock, etc. the stable door after the horse has bolted成語所屬單字doorclose, lock, etc. the stable door after the horse has boltedclose, lock, etc. the stable door after the horse has bolted — 慣用語慣用語1. To try to prevent a problem after it has already happened.1.慣用語釋義亡羊補牢To try to prevent a problem after it has already happened.例句Installing a security system after the theft is locking the stable door after the horse has bolted.Apologizing now is like closing the stable door after the horse has bolted.