In Du Fu's early poems (before the age of 40), most of them described the magnificent mountains and rivers and expressed their feelings. From the tenth year of Chang 'an, his poems began to turn to civilians. Chedian is his first-hand poem describing ordinary people, which gradually formed the style of "depressed and frustrated" and "worrying about the country and the people" in From Beijing to Fengxian. Later poems, including "Traveling to the Southwest as an Official", paid attention to the common people, but they couldn't let go of the rulers, so there were some contradictions in their hearts.