虽然对大多数历史学家来说，根据重要性对历史原因进行排序的必要性似乎是显而易见的，但这种等级制度引发了严重的哲学难题。

While the need to rank historical causes in some order of importance may seem obvious to most historians, such hierarchies raise serious philosophical difficulties.

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然而，很少有人意识到基本技能的重要性。如图所示，班上的学生正在质疑学习诸如乘法表这样的基本技能的必要性。

However, few people realize the importance of basic skills. As is shown in the picture, the pupils in the class are questioning the necessity of learning basic skill such as multiplication table.

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普通工人是非常重要的，他们被视作我们社会的必要组成部分。

Common workers are very important and they're considered the necessary part of our society.

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We have to adjust our understanding of his physical size one more time, and of course necessarily his moral magnitude would be adjusted as well in our interpretation.

当然必要的是，在我们的解说中他在道德上的重要性,也会随之调整。

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