单选题
The United States is well known for its network of major highways designed to help a driver get from one place to another in the shortest and possible time.
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these wide modern roads are generally
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many well maintained, with
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sharp curves and many straight
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, a direct route is not always the most
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one. Large highways often pass
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scenic areas and interesting small towns. Furthermore, these highways generally
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large urban centers, which means that they became crowded with
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traffic during rush hours,
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the "fast, direct" route becomes a very slow route. However, there is
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always another route to take
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you are not in a hurry. Not far from the
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new "superhighways" there are often older
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of heavily traveled roads which go through the countryside.
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these are good two-lane(双重音) roads; others are uneven roads
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through the country. These secondary routes may go up steep slopes, along high
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, or down frightening hillsides to towns
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in deep valleys. Through these less direct routes, longer and slower, they generally go to places
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the air is clean and the scenery is beautiful, and the driver may have a
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to get a fresh, clean
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of the world.