power-train

例句：

1. 1. The power-train is responsible for transmitting the engine's power to the wheels.
   动力系统负责将发动机的动力传递到车轮。
2. 2. The car's power-train was designed to be lightweight and efficient.
   这款汽车的动力系统设计得既轻便又高效。
3. 3. The new model uses a more powerful engine with a better power-train.
   新款模型使用了更强大的发动机，并采用了更好的动力传动装置。