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a group or chain of islands


a natural depression in the surface of the land often with a lake at the bottom of it


long and narrow strip of water made for boats or for irrigation


deep and narrow valley with steep walls


a strip of land projecting into a body of water


lake used to store water for community use


an area of high, flat land


flat, low-lying land built up from soil carried downstream by a river and deposited at its mouth


the point where a stream or river issues into a larger body of water


large area of level or rolling land with grass but few or no trees


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


a submerged ridge of rock or coral near the surface of the water


area of level land, usually at low elevation and often covered with grasses

rain forest

dense forest that receives high amounts of rain each year


land surrounded by water on three sides


a fertile tract in a desert (where the water table approaches the surface)


a large ice mass that moves slowly down a mountain or over land


an arm of a sea or ocean partly enclosed by land


a relatively narrow strip of land (with water on both sides) connecting two larger land areas


a flat grassland in tropical or subtropical regions


Treeless plains, especially the high, flat expanses of northern Eurasia, which usually have little rain and are covered with coarse grass.


a narrow channel of the sea joining two larger bodies of water


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

Tropic of Cancer

a line of latitude about 23 degrees North of the equator, the farthest point north where the sun is directly overhead at noon

Tropic of Capricorn

a line of latitude about 23 degrees South of the equator, the farthest point south where the sun is directly overhead at noon

Arctic Circle

Latitude 66.5 N, marking the southern boundary of that portion of the N. Hemisphere that receives a 24 hour period of sunlight once each year - occurs on June 22.

Antarctic Circle

Latitude 66.5 S, marking the northern boundary of that portion of the S. Hemisphere that receives a 24 hour period of sunlight once each year - occurs on December 22.

Prime Meridian

line of the global grid running from the North Pole to the South Pole through Greenwich, England; starting point for measuring degrees of east and west longitude


an imaginary line around the Earth parallel to the equator


a line of longitude

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