【答案解析】[听力原文] {{B}}Roads{{/B}} The United States is covered with a network of major highways/designed to help a driver get from one place to another in the shortest possible time . /Although these wide modem roads are generally smooth and well-maintained,/with few sharp curves and many straight, even stretches , /a direct route is not always the most enjoyable one .Large highways often bypass scenic areas and interesting small towns./Furthermore, these highways generally connect large urban centers , /which means that they become clogged with heavy traffic during rush hours , /when the "fast, direct" way becomes a very slow mute./ Unless time is short, there is almost always an alternate route./Not far from the relatively new superhighways , /there are often older, less heavily traveled roads , /sometimes marked as "scenic routes", which go through the country side. /Though these less direct mutes are usually longer and slower,/they generally go to places where the air is clean and the scenery is beautiful.