Why does Liu appreciate Cheng Liang's friendship?

I think Cheng Liang deserves respect and admiration. According to the information about Liu Shizhong, Liu Shizhong was a famous writer and calligrapher in the Tang Dynasty, and Cheng Liang was also a cultural celebrity in the Tang Dynasty. According to "All Tang Poems", Liu Shizhong once appreciated Cheng Liang's friendship, mainly because he was literary and noble. Cheng Liang is a famous writer in Tang Dynasty, who is famous for his fresh writing, fluent writing and lofty style. He is also a caring and righteous man, who often helps the poor with his own property and actively participates in the reform. Therefore, Liu appreciates Cheng Liang's friendship, because he thinks that Cheng Liang has both literary talent and noble moral character, which deserves respect and admiration.