He was already buffing the car's hubs.他已经在擦汽车轮毂了。I greased front and rear hubs and adjusted the brakes.我在前后轮毂上都抹了润滑油，还调校了刹车。Shafts and hubs are usually fastened together by means of keys.轴和轮毂通常用键固定在一起....

n.轮毂( hub的名词复数 )，中心，中心所在...

hubs的音标：...