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Plow is a main tool of agricultural farming all over the world. The effects of using a plow are different when it connected with other component or with different designing ideas. The Chinese plows and those made in Europe and America are quite different in structures from the early time. The cover of share of the Chinese plows (lei si) was protruding with triangle shape while the European ones (made of tree trunk) were narrow plate share with a wide sunken moldboard shape. Coming with the iron age, the plows had to be fit with iron share. However the different of share shapes still reserved and inherited in their developing process. The development of both shares in various eras (with many historical figures of both plows) was compared and their principles of soil cracking and effects of ecology and economy were emphasized and evaluated.