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an area of the Earth's surface with a definite shape; mountains and hills are an example.


in geography, a huge section of Earth's crust.

plate tectonics

the theory that the Earth's crust is made of huge, slowly moving slabs of rock called plates.


an area that rises steeply at least 2,000 feet above surrounding land; usually wide at the bottom and rising to a narrow peak or ridge. Everest is one of the most famous examples.


a large area of flat or gently rolling land. They can be found in the Midwest.


according to scientific theory, a single landmass that broke apart to form today's separate continents; thought to have existed about 180 million years ago.


a triangular-shaped plain at the mouth of a river, formed when sediment is deposited by flowing water. The Nile River has one of the most famous deltas.


a narrow strip of land that has water on both sides and joins two larger bodies of land. The one in Panama is a famous example.


an area of land completely surrounded by water. Martha's Vineyard and Nantucket are examples


land nearly surrounded by water; usually on three sides. Florida is an example.


a large, mostly flat area that rises above the surrounding land; at least one side has a steep slope. the most famous is the Tibetan, called the "roof of the world."


elevated land with sloping sides and rounded summit; generally smaller than a mountain


A body of fresh or salt water of considerable size, surrounded by land.


a vast treeless plain in the arctic regions between the ice cap and the tree line


a large stream of water of natural origin which drains an area of land and flows into another river or body of water


a constructed channel filled with water used for navigation, irrigation, or drainage


broad, flat-topped landform with steep sides; smaller than a plateau


Extremely delicious Polish dumplings stuffed with potato filling, sauerkraut, ground meat, cheese, or fruit. They are usually semicircular, fried or boiled, and served with butter or sour cream.

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