But when the food was in contact with tile or wood, 48-70% of bacteria were.

但当食物与瓷砖或木头接触时，会有48% -70%的细菌（留在上面）。

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But when the emotion that leads to stiffening the lip is more intense, and involves strong muscle tension, facial feedback may heighten emotional response.

但是当导致嘴唇僵硬的情绪变得更加强烈，并导致肌肉强烈绷紧时，面部表情反应就可能会增强情绪反应。

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The fur trade kept nutria in check for decades, but when the market for nutria collapsed in the late 1980s, the cat-sized animals multiplied like crazy.

几十年来，毛皮贸易一直控制着海狸鼠的数量，但在20世纪80年代末，海狸鼠毛制品市场崩溃，导致这种猫大小的动物的数量疯涨。

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But when the others finally asked his opinion, he admitted that he wanted to continue taking care of the baby himself.

VOA: special.2009.06.06

But when the concentration in the alloy is 50/50 by mole, something magical happens.

但是当合金中的浓度,是1比1的时候，有些神奇的事发生了。

麻省理工公开课 - 固态化学导论课程节选

I knew the storyline before I went, but when the lights went down, and then the story came out.

我去看之前就知道故事情节了，但当灯光暗下来，演出开始，

歌剧魅影 - SpeakingMax英语口语达人

But when the final analysis happened, somehow, financial gain reigns out above the desire to do good.

NPR: A Local Perspective on the South Carolina Vote

But when the church-trained belter from Georgia unleashes his pretty, gritty tenor, he's no mere imitator.

NPR: A Bold Soul Man Gets Bolder

But when the outsider enters to do research, as Buechler did, a negotiation is called for.

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