Feng Yansi, a poet of the Five Dynasties and Ten Kingdoms, was the prime minister of the Southern Tang Dynasty. Talented, kindhearted , open-minded and tolerant, but "worry" is often seen in the words.
What is sorrow? Probably not knowing what the nature is, not knowing why it started, uncertain sorrow. It's the emotions that are confused and obscure without revealing, and can't get rid of and can't get rid of.