A gear train unit with a motor-generator having a first planetary gear mechanism, a second planetary gear mechanism, an input shaft, an output shaft, a first clutch, and a second clutch is disclosed. The first planetary gear mechanism includes a first sun gear, a first ring gear, and a first carrier. The second planetary gear mechanism has a second sun gear, a second ring gear, and a second carrier. The second sun gear is connected to the first sun gear. The input shaft is connected to the second ring gear. The output shaft is connected to both the first ring gear and the second carrier. The first clutch selectively connects and disconnects the first carrier to and from the motor-generator. The second clutch selectively connects and disconnects the first sun gear and the second sun gear to and from the motor-generator.