Instead of wheels, the carts have flat pieces of wood or iron, which slide along on the top of the snow.

这些地方的车, 装着木头或者铁的平板, 就用这些平板, 在雪地上面滑行。

The reason why it is called a crawler is of course, because it moves with tracks instead of wheels.

之所以叫履带车，当然是因为它是用履带而不是轮子移动的。

Instead of wheels though, the motorcycle powers a set of gears which as the bike speeds up, begin to turn a sharpened metal coil inside the cylinder.

不过，摩托车不是为车轮提供动力，而是为一组齿轮提供动力，当自行车加速时，齿轮开始转动气缸内的锋利金属线圈。