One of the problems when people get sick from food is that the simplest question is often difficult or even impossible to answer. Just what did the people eat that made them sick?

人们因食品而生病的其中一个问题是，其中最简单的问题通常很难或者不可能回答，那就是：人们到底食用了什么才生病的？

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Teachers at school to answer our difficult problems in learning to our great help.

在学校里老师为我们解答疑难问题，在学习上给于我们很大的帮助。

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He is a living, but is a literary man, with a difficult problems often are asking questions, unity and coherence in writing, no matter, he is asked to answer.

他是个理科生，但却是个极具文采的人，每每遇到难题，不管文理，一律发问，他都谦虚解答。

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