The so-called epigraph is the name of the tune on which China's lyrics are based, also known as the tone of words. Before the Song Dynasty, all the words were sung with music, some were filled with words according to the tune, and some were tuned according to the words. The name of this score is epigraph. Lyrics should not only conform to music sounds, but also conform to certain rules, that is, the rules of words, such as the number of words, the level of words, sentence patterns, rhymes and so on.
Die Lian Hua, epigraph name, was originally Tang Qu, and later used as epigraph. Its original name is Quetiaozhi, and it is also known as Golden Reel, Rolling Pearl Curtain, Wu Fengqi, Nanpu under the Moon, Drizzle Blowing the Pond, A Golden Basket, Fish and Water Together, and Butterfly Lovers.
In the Southern Tang Dynasty, Feng Yansi's "Six Poems of Butterfly Lovers Sleeping on a Green Tree" (A Yan Shu Ci) was the main body, consisting of 60 disyllabic words, two paragraphs, five sentences and four rhymes, and two other variants. Representative works include Li Yu's Wandering in the Leaves of Dieyao, Liu Yong's Dieqianwei and Su Shi's Diechunjing.