This poem describes the process of success through repeated training. Through the use of metaphor and analogy, perseverance corresponds to the running of the river, emphasizing the importance of continuous efforts and perseverance. The river keeps flowing, and after numerous twists and turns and obstacles, it finally melts into the sea, symbolizing success. No matter how many difficulties and challenges you encounter, as long as you make unremitting efforts, you will eventually reach the other side of success.