My hometown is covered with Mongolia, the land is covered with Chu ridges, surrounded by lakes, and there is no wall in the sky. According to Wuhan Education Cloud, the first four sentences of "seeing Sun Chengwei off to Beihai" are: My hometown is covered with Chu Ridge, with thousands of lakes and no walls around the sky. Seeing Sun Chengwei off to Beihai is a five-character poem written by Qin Guan in the Northern Song Dynasty, which depicts the vastness of gaoyou lake and Gaoyou's outstanding people.