Black hair doesn't know who the diligent and early author is, but regrets reading late.

"Black hair doesn't know how to study hard early, and Bai Shoufang regrets studying late." The writer is Yan Zhenqing, a calligrapher in the Tang Dynasty.

"Black hair doesn't know how to study hard early, and Bai Shoufang regrets studying late." From the Tang Dynasty calligrapher Yan Zhenqing's "Persuade Learning". The whole poem is: "Turn on the light at five o'clock in the middle of the night, just as the man is reading. I don't know how to study hard early, but I regret learning late. "