There is no standard in ancient vernacular. Due to the differences of dialects in different regions of Chinese, many kinds of vernacular Chinese have been derived. After the Qing Dynasty, the popularity of traditional Chinese opera and the communication between regions began to become more and more frequent. There are four kinds of operas that have been widely recognized and recognized at the earliest, namely, Bai Yun, Bai Jing, Su Bai and Bai Guang, also known as the Four Vernaculars.
During the Ming and Qing Dynasties, many dramas adopted various standard vernacular traditions, but they all changed and developed under the consideration of local pronunciation. The characteristics of * * * on the stage are not obvious. Generally speaking, some pronunciation and articulation methods are followed, and there is still a cadence and special rhythm when chanting. Generally speaking, this kind of chanting with Zhongzhou rhyme is called "Bai Yun" or "Shang Yun" to distinguish it from chanting with local dialects, such as "Bai Jing" and "Su Bai".