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Why is it that many teenagers have the energy to play computer games until late at night but can't find the energy to get out of bed (1) ________ for school? According to a new report, today's generation of children are in danger of getting so (2)_______ sleep that they are putting their mental and physical health at (3)_______. Adults can easily survive on seven to eight hours' sleep a night, (4)_______teenagers require nine or ten hours. According to medical experts, one in five youngsters (5)________ anything between two and five hours' sleep a night less than their parents did at their age.

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