A clutch for coupling an internal combustion engine in a torque-transmitting fashion and decoupling an internal combustion engine is disclosed. The internal combustion engine has a partial drive train that includes an electric machine. The clutch includes at least one adjustable element with which in conjunction with coupling means can be opened counter to a closing force generated by closing means. Locking means interacts with the adjustable element and has an adjustable locking element. The locking means interacting with the adjustable element in such a way that the coupling means are held open without an opening force having to be applied for this purpose by an adjustment means, or in such a way that the opening force which has to be applied by the adjustment means to hold the coupling means open is reduced.