In the Chinese tradition, the rainbow is a common symbol for marriage because the colours represent the union of yin and yang.

在中国的传统中，彩虹是婚姻的普遍象征，因为它的颜色代表着阴阳的结合。

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It's a common symbol in Maths.

这是数学中最常见的符号。

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Oak is a common symbol of strength.

橡树经常被看作力量的象征。

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Another common symbol that transcends various traditions is the exchanging of something during the ceremony.

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In this question, the relationship is simply that the symbols have nothing in common except that they are the same kind of symbol.

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As part of the closing, the company changed its name to Dominion Diamond Corp. and its common shares now trade on the Toronto and New York stock exchanges under the symbol DDC.

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