单选题
If you are writing or studying, it makes very much difference where the light comes from. People who use books and pens every day
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to be especially careful about the direction from which the light shines on their work.
A house gets it"s light
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from daylight through windows
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is very good to use or from the lamps, but no matter what kind of light it is, the direction it slants(倾斜) towards our books or our work is a matter of great
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to the eyes.
Take a book, stand with your back toward the window, and try to read. Your shadow falls across the page and makes it bad for your eyes as if you were in a
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room.
Now turn
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and face the window. The page is the shadow again, while the bright light is in your
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. Try standing with your right side towards the window. This is very good for reading,
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if you were writing, the shadow would
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the page and trouble you a little.
There is just one other way: stand with your
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side to the window. Now everything is perfect for reading and for writing, too.