Analyze the characteristics of Du Fu's poetic history with examples.

First, Du Fu's poems are widely used. He not only uses poetry to describe lyricism, but also uses poetry to write biographies and autobiographies, letters, travel notes, political comments and poetry reviews, which is almost omnipotent. However, it also brings about the problem that some poems tend to be rational.

Second, Du Fu's attitude towards the previous generation of poetry was more tolerant, and he advocated "benefiting from many teachers" instead of easily denying it. For example, although Du Fu also criticized the poems of the Southern Dynasties, he never boasted that "beauty is not precious since Jian 'an came" (one of the "ancient styles") like Li Bai. He sincerely affirmed and borrowed from many writers of the Six Dynasties, such as Yu Xin, He Xun and Yin Keng, thus enriching his own creation. This point was emphatically pointed out by Yuan Zhen in the Epitaph of Du Fu.