"But since the water is still flowing, although we cut it with the sword" comes from that poem. What is the whole poem like and how to understand it?

The poem expresses the anguish of wasted years and the ambition of rare reward, praises the articles in Hanshu, praises the heroism of Jian 'an and Xie Tiao's poems, and finally reveals the negative feelings of being born. The beginning of this poem seems abrupt. Why do you want to write like this? Because Li Bai was depressed at that time, he vented his dissatisfaction as soon as he saw his uncle Liu Yun who could talk to him. Li Bai sacrificed to the Hanlin in Tianbao, but he was not taken seriously politically and was vilified by powerful people. Before long, he abandoned his official position and lived a vagrant life. The bitterness of the past ten years, the depression and sadness of traveling abroad are all accumulated in my heart, and today I can finally get it off my chest. The words "Changfeng" are lyrical by the scenery. When you look at the autumn geese, your spirit does it one brace up and your troubles are swept away. I feel comfortable in my heart and environment, and I feel proud of drinking tall buildings. Penglai is a farewell dinner for high-rise buildings, written separately by the host and the guest. Praise Li Yun's writing style with Jian 'an Bone. "China is the guiding direction" refers to Xie Tiao, because he is Xiao Xie after Xie Lingyun. Here, Li Bai compares himself with Xiao Xie, showing his confidence in his talents. It is strange and creative to use the word "drawing a sword" to describe the inner anguish that cannot be solved. The phrase "raising a glass" expresses his depressed mood that he can't get rid of and can only worry. The last two sentences are the poet's angry words about the reality. Li Bai, who has been in the depression of dissatisfaction for a long time, has to seek another kind of detachment, that is, "sending a boat." Although he didn't mean to escape from reality, the historical conditions at that time and his lofty and indulgent personality prevented him from finding a better way out.