阅读下面短文,回答问题。
Why do people cry? Scientists say the body produces tears because they need them. One kind of tears is for the eye, the other is for the heart. They both work as cleaners. If something else like dust(灰尘) gets into your eye, tears also come into the eye to clean it out. If you are hurt by something, your strong feelings produce some poisonous chemicals(毒素) in your body, and at the same time, tears come out with them. If these poisonous chemicals are not cleaned out of your body as soon as possible, they will do harm to the heart sooner or later.
In the United States men have heart problems more often than women do. Doctors say heart problems have something to do with the pressures(压力) of living and working now. Perhaps men suffer more from these illnesses because they do not cry enough. They need to cry more.
In fact, you can find many ways of reducing the pressures to keep fit. Crying is a natural and physical one.
30. How many kinds of tears does the body usually produce?
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31. What do tears do when dust gets into your eye?
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32. Will the poisonous chemicals in the body do harm to the heart?
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33. Why do men suffer more from heart problems than women?
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34. What will you do to reduce the pressures of living and working to keep fit? Please give TWO examples.
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