The United States of America, also called America, the States, the US, or Uncle Sam, is so vast in size and so complex in its ethnic origins that it seems to defy any kind of compact generalization. The United States is 9, 372, 614 km2 in size, with its continent extending 4, 505 km east to west, 2, 574 km north to south. The Great Lakesthe biggest body of fresh water in the world The Grand Canyon(大峡谷)Intermountain Region The mountains, hills, plateaus(高原), and plains of Nort
