If you take a glimpse at the map of the United States, you will find major cities scattered on her eastern and western coasts. If you take a (1) over these cities at night, you will have an illusion that there were (2) glittering on the horizon, (3) colorful and brighter than (4) in the sky.
Starting from settlements of early (5) , villages and small towns have developed, (6) and modernized. Now over 70 percent of the nation’s (7) reside in metropolitan areas (8) only one percent of the nation’s land area. The American (9) house the might of her industries, activities of her (10) enterprises and daily (11) of her financial institutions. (12) , academic institutions and cultural facilities (13) locate in her major cities. (14) , they are the glittering diamonds on the crown of the U.S. empire.
But the American cities become the (15) of their development. They are now decaying and dying. As they grow, residents are (16) constantly by overcrowded streets, traffic (17) , pollution, housing shortage, crime, drug indulgence and other urban (18) . People then try to seek a tranquil, clean and safe place to live in. A trend (19) "deurbanization" began at the turn of this century when residents of middle class—most of them were whites—move out of the (20) downtown to the suburbs and set up their residential zones.

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