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When can people think about our eyes very often?
On the time when we ______.
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What things can nearsighted people see clearly?
Things which are very ______ their eyes?
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Who will become nearsighted easily?
People who do a lot of ______ will become nearsighted easily.
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Why do nearsighted people wear glasses?
In order to see ______.
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What problem do farsighted people suffer from?
They have difficulty seeing ______.