Wang Guowei's textual research on Song and Yuan operas holds that "the independent Yuan zaju was narrated in Bai Ke, while Wen Qu was an endorsement ... both of them made progress in form and material, and then the real drama of our country came out."
Yuan Zaju, also known as North Zaju, is a kind of Han opera sung in North Qu in Yuan Dynasty. It was formed at the end of Song Dynasty and flourished in Dade period of Yuan Dynasty (1the second half of 3rd century-14th century). The main representative writers are Guan Hanqing, Zheng Guangzu, Ma Zhiyuan and Bai Pu. The main representative works are Dou Eyuan, Autumn in the Han Palace, Strange Tales from a Lonely Studio and Wu Tongyu.
Its content focuses on exposing social darkness and reflecting people's sufferings, combining realism with romanticism, with clear main lines and distinctive characters. Its structural characteristics are four folds and one wedge, and "one person is the lead singer". The roles of zaju are divided into Dan, Mei, Jing and Za.