三个一组的，三重的。

Composed of three or arranged in threes.

youdao

三个组成的由三部分组成的，三个一组的，三重的。

Consisting of three parts or proceeding by threes; ternary.

youdao

很少的韩国人知道三个一组的前外一周半跳和三个后内结环一周跳的差别。

Few South Koreans know the difference between a triple axel and a triple salchow.

youdao

There are 64 combinations of three bases and I only need to describe 20, so there's combinations to spare.

三个一组的碱基产生六十四种组合,而我只需对应二十种氨基酸,所以一种氨基酸会对应不同密码子

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