A workpiece applied for a cutting machine, wherein the workpiece includes a first arm, a second arm and at least one connection hole, an angle between a first plane having a first-arm axial line and a second plane having a second-arm axial line being ranged between 0° and 180°; wherein the workpiece is fixed to an object of the cutting machine by using a fixation part in combination with the connection hole; wherein the workpiece at least includes a first outer surface, a second outer surface and a third outer surface, the third outer surface intersecting the first outer surface and the second outer surface to define a first extrusion-acting portion; characterized in that the first extrusion-acting portion is formed laterally to the first arm and includes a first extruding portion; a front end of the second arm is formed to be a second extrusion-acting portion which includes a second extruding portion; the first and second extrusion-acting portions are configured to be guiding the workpiece or extruding or polishing upon the surface machined by the blade portion; wherein the workpiece further includes a first blade portion located at a front end of the first arm, wherein the workpiece is configured so that the first blade portion firstly performs cut-machining upon the object, and then the first extruding portion performs extruding upon the object and the first extrusion-acting portion is configured to be guiding the workpiece or extruding or polishing upon the surface machined by the first blade portion; wherein the workpiece further includes a second blade portion located laterally to the second arm, wherein the workpiece is configured so that the second blade portion firstly performs cut-machining upon the object, and then the second extruding portion performs extruding upon the object and the second extrusion-acting portion is configured to be guiding the workpiece or extruding or polishing upon the surface machined by the second blade portion. the first extrusion-acting portion is formed laterally to the first arm and includes a first extruding portion; a front end of the second arm is formed to be a second extrusion-acting portion which includes a second extruding portion; the first and second extrusion-acting portions are configured to be guiding the workpiece or extruding or polishing upon the surface machined by the blade portion; wherein the workpiece further includes a first blade portion located at a front end of the first arm, wherein the workpiece is configured so that the first blade portion firstly performs cut-machining upon the object, and then the first extruding portion performs extruding upon the object and the first extrusion-acting portion is configured to be guiding the workpiece or extruding or polishing upon the surface machined by the first blade portion; wherein the workpiece further includes a second blade portion located laterally to the second arm, wherein the workpiece is configured so that the second blade portion firstly performs cut-machining upon the object, and then the second extruding portion performs extruding upon the object and the second extrusion-acting portion is configured to be guiding the workpiece or extruding or polishing upon the surface machined by the second blade portion.