"the red under the glaze first began in the Yuan Dynasty, and it was brilliant for a period of time in the early Ming Dynasty, and then it was brilliant again in the Kangxi, Yongzheng and Qianlong periods of the Qing Dynasty. With the end of the prosperous period of Kangxi and Qianlong, the red under the glaze came to an end. Although the period of Yongzheng (1723-1735) was short, it was characterized by economic development, social stability and rapid progress in porcelain making. According to the archives of the Office of the Qing Palace, Emperor Yongzheng himself repeatedly stipulated the shape and pattern of porcelain, which required not only the appropriate size of each part of the fired porcelain, but also the momentum and charm, and the rhythmic beauty of the outline lines. The imperial porcelain to be burned must be examined and approved by Emperor Yongzheng before it can be fired. According to the will, Nien Xiyao and Tang Ying, the pottery supervisors of Jingdezhen Imperial Kiln Factory, gathered the best porcelain craftsmen in the country, spared no expense and tried their best to burn it, so as to win the favor of the emperor and made unprecedented brilliant achievements. It should be said that the aesthetic taste of Emperor Yongzheng played a decisive role in the modeling and painting style of porcelain in this period. "