Who says that old people will never return to their youth? Look, the running water in front of that door can still flow west! Therefore, don't lament the passage of time when you are old.

Youth is only once for people, as the ancients said: "Flowers bloom and fall, and no one is perfect." This is an irresistible natural law. However, in a sense, people can't be old and vigorous, and the spirit of self-improvement can often glow with youthful brilliance.