偶数规则（even number rule）：元素周期表中相邻的两元素，原子序数为偶数的，其在地壳中的平均含量常大于奇数元素的含量。
游戏的规则是：“如果某张卡片上的数字是偶数，那么另外一边便是红色。”
The rule to be tested is: “If a card shows an even number on one side, then it is red on the other.
游戏检验的规则是：“如果一张卡片展示的是偶数，那么另一张卡片就显示红色。”
The rule to be tested is: “If a card shows an even number on one side, then it is red on the other.”
遵循标准数独规则，每个胶囊里面有一个奇数和一个偶数。
Apply classic Sudoku rules. Each capsule contains one odd number and one even number.
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