1. He used to be a bad student but turned out to be a late boomer when he became a successful businessman.2. When he's young he used to waste time by playing games. When he got older he got his act together and became successful.
 sleeper a late boomersleeper 指一開始不成功後來卻很成功, 可以用在書, 電影, 人等. 通常白話翻譯. late boomer 指一個人到長大才突然展現過人的能力.
The janitor neglected his duty on the day the robbers brok into the school.