reflecting boundary

例句：

1. 1. The scientist used a mirror to observe the reflected boundary of light.
   科学家用镜子观察光线的反射边界。
2. 2.The boundary between two cultures is often marked by language and customs.
   两种文化之间的边界通常由语言和习俗来标记。
3. 3. The researcher found that the boundary between knowledge and belief was blurred in this new study.
   研究者发现，在这项新的研究中，知识与信仰之间的界限变得模糊了。