1, black hair doesn't know how to study hard early, but it's too late to learn. -Yan Zhenqing's "Encouraging Learning" in the Tang Dynasty

Teenagers don't know how to get up early and study hard. When they are old, it will be too late to regret reading less.

2, don't wait, white young head, empty and sad. -Yue Fei's "Man Jiang Hong" in the Southern Song Dynasty

Don't waste your time, only regret it alone.

3, youth must be early, how can you grow into a teenager. -Meng Jiao's "Encouraging Learning" in the Tang Dynasty

You should work hard as soon as possible while you are young. Can a person be a teenager forever?

4. If young people don't work hard, old people will be sad. -"Long Songs" anonymous Three Kingdoms period

If you don't work hard when you are young, you will achieve nothing when you are old. It will only increase your sadness and it will be too late to regret.

5, the book is used, I am not so annoying, I don't know it is difficult to do things. -"Augmented Sage"

When it comes to practical application, I regret that I have read too little and have not experienced the difficulty of not knowing things.