invariant plane

例句：

1. 1. The physicist used the invariant plane to solve the problem.
   物理学家使用不变平面解决了这个问题。
2. 2.The scientist discovered a new invariant plane that could be used for navigation.
   科学家发现了一种新的不变平面，可以用于导航。
3. 3.The invariant plane was used as a reference point for measuring angles.
   不变平面被用作测量角度的参考点。