By the improvement of demonstration experiment on optics, we able to observe the optical path and further understand to optical principle.
通过对光学演示实验的改进，使我们能够观察到光路，加深了对光学原理的理解。
The principle of sympathy is an important path by which moral sense arise and produce effects.
同情原则是道德感产生和发生作用的重要途径。
The NLOS sound signal usually arrives at acoustic array by diffraction, and the diffracted transmission path is a geodesic according to the extensive Famat's principle.
非视距声信号通常经过绕射到达基阵，根据广义费马原理，传播路径为一条短程线。
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