He ate the fish raw, masticating with painstaking care, for the eating was an act of pure reason.

他把鱼生吃下去，费劲地咀嚼着，因为吃东西已成了纯粹出于理智的动作。

During the human evolution, the masticating apparatus have been weakened by the changes of producing and living style.

在人类长期的演化过程中，随着生产生活方式的改变，人类的咀嚼器官总体呈现出一个逐渐退化的趋势。