axial musculature

例句：

1. 1. The axis of the planet revolves around its center.
   行星的轴线围绕其中心旋转。
2. 2. The axis of the machine is located at the bottom.
   机器的轴线位于底部。
3. 3. The axis of the Earth's rotation is vertical.
   地球自转的轴线是垂直的。