axial acceleation

例句：

1. 1. The machine has an axial gear system that allows it to rotate smoothly.
   这台机器有一个轴齿轮系统，可以平稳地旋转。
2. 2. The axis of the planet revolves around its center.
   行星的轴心围绕其中心旋转。
3. 3. The axis of rotation is perpendicular to the plane of the earth's orbit.
   旋转轴垂直于地球轨道平面。