Multifunctional reciprocating saw and using method

The invention discloses a multifunctional reciprocating saw, The multifunctional reciprocating saw comprises a first box body, wherein a trigger cavity, a transmission cavity and a working cavity are sequentially arranged in the first box body from left to right, the inner wall of the working cavity is slidably connected with a concentric-square-shaped frame, the inner wall of the left end of the working cavity is rotatably connected with a first rotating shaft penetrating through the inner wall of the right end of the working cavity, the first rotating shaft is rotatably connected with the right end of the working cavity, and the first rotating shaft is located in the concentric-square-shaped frame. The multifunctional reciprocating saw has the beneficial effects that the structure is simple, operation is easy and convenient, auxiliary marking lines can be regularly marked on the surface of a plate during sawing, people can rapidly align the auxiliary marking lines during sawing, the reciprocating saw does n