| A | B |
| plateau | a large raised area of mostly level land |
| isthmus | a strip of land with water on both sides that joins two larger bodies of land |
| pampas | flat grassland regions |
| rain forest | a dense evergreen forest that has abundant rainfall year-around |
| Amazon River | a long river in northern South America |
| tributary | a river or stream that flows into a larger river |
| Middle America | Mexico and Central America |
| El Nino | a warming of the ocean water along the western coast of South America |
| elevation | the height of land above sea level |
| economy | the ways that goods and services are produced and made available to people |
| natural resources | things found in nature that people can use to meet their needs |
| hydroelectricity | electric power produced by rushing water |
| one-resource economy | a country's economy based largely on one resource or crop |
| diversify | to add variety |