2, from the Tang Dynasty Yan Zhenqing's "Persuasion".
3, the original text: the light is midnight at 5 o'clock, just when men are reading. Teenagers only know how to play, but don't know how to study hard. When they are old, they regret why they didn't know how to study hard when they were young.
Midnight is the best time for boys to study every day. Teenagers don't know how to get up early and study hard, and it will be too late to regret reading less when they are old.
5. Yan Zhenqing (August 23, 709-784) was born in Jingzhao Wannian (now Xi 'an, Shaanxi) and Linyi (now Linyi, Shandong). Yan Shigu V was a famous official, calligrapher and secretary supervisor in the Tang Dynasty. He was once a famous painter such as Sun and Situ. Yan Zhenqing's calligraphy is exquisite and good at it. Chu Suiliang, a beginner, studied under Zhang Xu and got his brushwork. Its regular script is dignified and majestic, and its running script is vigorous and powerful, which has created a "Yan style" regular script and has a great influence on later generations. Together with Zhao Mengfu, Liu Gongquan and Ou Yangxun, they are also called "four masters of regular script". Together with Liu Gongquan, they are called "Yan Liu" and "Yangu".