A middle school student is addicted to online games and cannot extricate himself. His parents and relatives tried hard to persuade him, but they still failed to make him understand the dangers of being addicted to online games. This is really: the lights are brighter at midnight, and the lights are brighter at dawn. When a boy is studying, he will be too late to study hard if he is black-haired. (Please fill in the verses) In response to this phenomenon, can you use appropriate famous aphorisms or sentences from the Analects to admonish him, so that he will cherish time and study diligently in his future life? Please write on the horizontal line.

A middle school student is addicted to online games and cannot extricate himself. His parents and relatives have tried hard to persuade him, but they have never been able to make him understand the dangers of being addicted to online games. This is really: one mistake will lead to eternal regrets, and it will never look back again. A hundred years old.