What is the perfect unity of form and function in the design of China handicraft era?

In the design of China handicraft era, the perfect unity of form and function was realized from three aspects: function, modeling and decoration. Fine loess should be selected to remove impurities. If high temperature firing is needed, sand should be mixed to prevent dry cracking. Pottery was originally made by hand. For larger objects, it was rolled into clay strips and then rolled into the shape of a vessel. Later, it gradually developed into wheel molding. During Yangshao culture period, there was a primary form of pottery wheel with simple structure and slow rotation, which was generally called slow wheel. At that time, the molding, trimming and even some decorative patterns of pottery were made with the help of this slow wheel.