the United States is well konwn for its network of major hig

the United States is well konwn for its network of major highways 的完形填空

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 possible time. Although these wide modern roads are generally smooth and well maintained, with few sharp curves and many straight sections, a direct route is not always the most enjoyable one. Large highways often pass by scenic areas and interesting small towns. Furthermore, these highways generally connect large urban centers which means that they become crowded with heavy traffic during rush hours, when the "fast, direct" way becomes a very slow route. However, there is almost always another route to take if you are not in a hurry. Not for from the relatively new "superhighways", there are often older, extremely heavily traveled roads which go through the countryside. Some of these are good lane roads; others are uneven roads curving through the country. These secondary routes may go up steep slopes, along hilly cliffs or down frightening hillsides to towns lying in deep valleys. Though these are less direct routes, longer and slower, they generally go to places where the air is clean and the scenery is beautiful, and the driver may have a chance to get a fresh, clean view of the world.