Ctrl+Shift+S is saved as a file in. Dxf format. According to the introduction of Pacific Computer Network, Ctrl+Shift+S needs to be saved as a file in. Dxf format, used for ivy printing, to remove the imprint of education edition. Dxf and dwg display in different ways, which is easy to identify. Open the dxf file you just saved, save it as dwg file again, reopen it, and then print it, so there will be no educational stamp.