A clutch includes a drive disc, a driven disc, and a friction plate unit capable of engaging or disengaging the drive disc with or from the driven disc, the friction plate unit including a first friction plate assembly and a second friction plate assembly, the clutch further including a pressing unit configured to engage or disengage the drive disc with or from the driven disc selectively by the first friction plate assembly alone or by a combination of the first friction plate assembly and the second friction plate assembly. Such an arrangement enables the clutch to select an appropriate number of friction plates as required for engagement, solving the problem that in existing multi-plate clutches, it is impossible to select an appropriate number of friction plates to participate in work to make the clutches obtain optimal performance according to different working conditions of the automobile.