我需一份美国的英文简介

The United States of America is a country of the western hemisphere, comprising fifty states and several territories. Forty-eight contiguous states lie in central North America between the Pacific and Atlantic Oceans, bound on land by Canada to the north and Mexico to the south; Alaska is in the northwest of the continent with Canada to its east, and Hawaii is in the mid-Pacific. The United States is a federal constitutional republic; Washington, its capital, is coextensive with the District of Columbia (D.C.), the federal capital district.

At over 3.7 million square miles (over 9.6 million km²) and with over 300 million people, the United States is the third or fourth largest country by total area and third largest by population. With a gross domestic product (GDP) of over $13 trillion, the U.S. has the largest national economy in the world. GDP per capita ranks first among the larger economies of the world, and third or eighth overall, depending on the measurement.