Why can the song "Su Wu Shepherd" be passed down from generation to generation among the people?

The tune of this word comes from the folk song No.1, just like the ancient Mulan Ci. In 196, when the Qing court sent Weng Ceng Kun to the Xing 'an Mountains to survey the Sino-Russian border, he was plundered by Russia and imprisoned in a place called Miaojie. Weng Ceng Kun was unyielding, and he remembered that Su Wu, who was sent to Xiongnu in Han Dynasty, was also imprisoned in Beihai. Therefore, I wrote a song "Su Wu Shepherd" to encourage myself. "Su Wu leave Hu Jie, snow and ice, suffering for 19 years. Thirst for snow, hunger for blankets, herding sheep on the North Sea. I'm worried about the Han state, but I haven't returned it yet. After going through difficulties, my heart is as strong as stone. It hurts to hear the creaking when you sit in the traffic jam at night. In a blink of an eye, the north wind blows and the geese fly. White-haired Niang, looking forward to her son's return, red makeup keeps empty. In the third night, we dream together, but who will sleep in both places? Let the seas run dry and the rocks crumble, and the big festival will not hurt. Finally, I taught the Huns to be frightened and bow down to Han Dewei. " During the 5th birthday of Wu Peifu, a great warlord in the Republic of China, Su Wu Shepherd was chosen as the birthday song. The score was the tune of the number one song, but it was filled with deep and tragic emotions, and the singing speed slowed down, which became the ancient song Su Wu Shepherd that we often heard. Due to the reasons of the times, resisting foreign invasion and propagating national spirit made Su Wu sing, but few people sang the number one song again. It is precisely because of the songs sung by the people (because what is good and meaningful will be circulated by the people) and the meaningful story of Su Wu's shepherd that Su Wu's shepherd has such vitality. However, the lyrics of the number one song at that time were also very meaningful: "Cao's family has a good boy, who will never forget it, and everyone praises him as a prodigy." Respect teachers, know etiquette, and filial piety spreads to thousands of families. Be ambitious when you are young, and report to the country when you are successful. Twice in the lift, the golden palace folded the laurel head and inserted the flower. I have been to the Qionglin Banquet and rode on the Imperial Street. The academician courtyard, a college student, accompanied him in the court. Toward Optimus Prime, across the sea purple gold beam. Rong Zongyaozu, who does not envy Cao's family? "