three-dimensional polar curves

例句：

1. 1. In the three-dimensional polar curves, the shape of the object is determined by its position and orientation in space.
   在三维极坐标曲线中，物体的形状由其在空间的位置和方向决定。
2. 2. The three-dimensional polar curves are used to describe the shape and motion of objects in space.
   三维极坐标曲线用于描述物体在空间的形状和运动。
3. 3. The three-dimensional polar curves are essential for understanding the behavior of complex systems in nature.
   三维极坐标曲线对于理解自然界复杂系统的行为至关重要。