Paper is made of fibers, and the gaps between fibers are very small, forming countless very fine capillaries. The principle of paper stretching is that paper is made of fibers, and the gaps between fibers are very small, thus forming countless tiny capillary paper-cuts. Stretching is a kind of paper-cutting, and it is relatively easy to master the shape. It integrates several processes such as folding (rolling), cutting, bending and painting. It is a popular art form and a three-dimensional modeling of paper-cutting.