There are three obvious changes in the Wu Li calligraphy:the first is the Su Shi regular script in 1659-1668,the second is the 1668-1672 transition from Su Shi to the small-character regular script of Wang Xizhi,Zhao Mengfu,and Ni Zan,and the third is the return to Su Shi,throughout the 1674-1675 period,and the subsequent gradual shift to running script.Three subsequent distinguishing traits of Wu Li's writing habits include the fact that his characters tend to skew towards the upper right corner,characters tend to be flat with short vertical and long horizontal strokes,while later characters are built with thin vertical,thick horizontal,and strong left-falling strokes.The evolution of this general physiognomy in each period roughly constitutes the basic evolutionary pattern of Wu Li's writing style,and may thus effectively solve the problem of dating his undated works.