Within each of these cylinders is a piston, which moves up and down, spinning a bar known as a crankshaft, effectively converting linear motion into a rotary motion that can drive the wheels.

每个气缸内都有一个活塞，活塞上下移动， 旋转一根称为曲轴的杆，有效地将线性运动转换为可以驱动车轮的旋转运动。