首先被磨平的区域会集中在第一个凹槽，而同时第二层凹槽又抵消了剥削的力。

The wear flat tends to stay within the area of the first chamfer, with the second chamfer providing extended protection against chipping and spalling.

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但凡少年，除却顽劣的脾性，没被世俗磨平的棱角，还有一点，即那分明的爱憎。不明所以又理所当然的爱憎。

Every child, besides some tough temper, some rough edges just not be smoothed by secularity, there is another thing, namely, the kind of clear-cut love and hate which had no reason and so happened.

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时代转变体现在细节上，比如，一面能清晰反映人们面容的镜子，过去日本人只能使用磨平的铜镜，而那个时代已经逝去。

For example, everyone was fascinated by the new glass mirrors that showed their faces so clearly; before then, the Japanese used only dim bronze.

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