"三更灯火五更鸡,正是男儿读书时.黑发不知勤学早,白首方悔读书迟."

诗词：劝学
作者：颜真卿

三更灯火五更鸡，
正是男儿读书时。
黑发不知勤学早，
白首方悔读书迟。

Yan Zhenqing
From Wikipedia, the free encyclopedia

Yan Zhenqing (颜真卿, 709–785) was a leading Chinese calligrapher and a loyal governor of the Tang Dynasty.

His artistic accomplishment in Chinese calligraphy parallels the greatest master calligraphers throughout the history, and his calligraphy style, Yan, is the textbook-style that every calligraphy lover has to imitate today.