Optical depth and optical path are often confused in the literature. 文献中光学厚度和光程时常混淆。
In a successful marriage ,there is no such thing as one's way,there is only one way for both ,only the bumpy,dusty,difficult,but always mutual path. 在成功的婚姻中，没有谁自己的路的说法，有的只是两个人的路，或许崎岖不平，风尘满程，困难重重，却永远是两个人共同的路。
