If a category always drills to one and only one category then the two levels should be merged.
如果一个分类总是属于一个且只属于一个分类，那么这两个层次就应该合并。
Only significant changes in elemental impurity levels, leading to a different conclusion should be reported.
只有当元素杂质水平有重大变更时，才会需要报告其导出的不同结论。
Just because there will be problems anyway does not mean you should launch prematurely; doing so will only scale up your difficulties to unmanageable levels.
仅仅因为总会遇到困难不意味着你可以提早发行，这么多只会让你将要遇到的问题成倍的增加到无法处理的地步。
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