homotopy addition theorem

例句：

1. 1.The two shapes are homotopically equivalent.
   这两个形状是同胚的。
2. 2. In mathematics, the concept of homotopy is fundamental to understanding the behavior of curves and surfaces.
   在数学中，同胚的概念对于理解曲线和曲面的行为至关重要。
3. 3.The study of homotopy has applications in many fields, including computer graphics and robotics.
   同胚学的研究在许多领域都有应用，包括计算机图形学和机器人学。