axil

例句：

1. 1. The machine's axis is perfectly aligned with the table.
   这台机器的轴线与桌子完美对齐。
2. 2. The axis of rotation is perpendicular to the plane of rotation.
   旋转轴垂直于旋转平面。
3. 3. The axis of symmetry is the line that divides the object into two equal parts.
   对称轴是将物体分成两部分的线。