This process of using a biological event like resistance to Ampicillin in order to pick out the cell population that you're interested in is called selection.

这个利用生物特性,如对氨苄青霉素的抗性,来挑出你所感兴趣的细胞的过程叫筛选

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In another example, you can use a "when" question in order to ask about the timing of a specific event.

在下面这个例子中，你可以用When 问句来询问一个具体活动的时间。

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In order to understand probability, you have to take things as coming from a random event and people don't clearly have that in their mind from an intuitive standpoint.

为了理解概率,你要把事件想象成是随机发生的,但人们没有那样,清晰直观的认识

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