Why did so many ballads spread in the early days of the Liberation War?

War is both military and political, and politics is propaganda and influence. Most people in old China could not read. If you write posters and slogans or distribute pamphlets and leaflets, not many people can understand them. Even if the Communist Party of China (CPC) and the Kuomintang were engaged in literacy everywhere, it would be impossible to popularize traditional Chinese characters quickly, so the Communist Party of China (CPC) thought of a way. That is, by writing jingles and short songs, most people can't read, but most people listen to songs and sing, thus achieving the purpose of publicity.