Provide samples of previous signatures, compare the general characteristics of samples and samples, such as font style, handwriting size, text layout, size collocation, writing level and proficiency, as well as the detailed characteristics of the same word, such as stroke movement, stroke order, Lian Bi, the proportional relationship of the cross position of stroke length, the collocation relationship of components, the change of stroke strength, etc., and then draw a conclusion. If it is imitation, there will be some differences in the above characteristics.