1. It's just that when a man is studying, his black hair doesn't know that he is diligent and early, and his white hair regrets that he is late. -Yan Zhenqing

2. An inch of time is worth an inch of gold, but an inch of gold cannot buy an inch of time.

3. It is difficult for a teenager to learn and grow old, and an inch of time is not light. -Zhu Xi

4. My life is limited, but so is my knowledge. -Zhuangzi

5. If a young man doesn't work hard, the old man will be sad. -"Long Songs"