They are RNA molecules but they have at some points in their life span, they have amino acids attached to them.

这些是如假包换的RNA分子,但在其生命周期的特定时间,它们会携带一个氨基酸分子

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In another example, you could explain what you're doing not only at a particular moment,

在下面一个例子中，你可以解释不仅仅在一个特定时间干的事情。

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> David: At some point in time, I'm going to have to have declared the variable as a float before I can then hand it to printf as the insertion value for that format strength.

>，大卫：在一个特定的时间，我将需要,声明float类型这样的变量,那样我就可以把它打印出来,像是格式化优点的插入值。

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