Caption: A picture of the Great Plains, west of Kearney, Nebraska.
Almost three-fourths of Earth is covered by oceans. A little more than one-fourth of our Earth is land. There are seven large masses of land called continents. Oceans and continents are landforms. A landform is a feature of Earth's land surface. There are several kinds of landforms. Three landforms are plains, mountains, and plateaus.
Plains are large, mostly flat areas of low-lying land. The middle part of the United States is called the Great Plains. The Great Plains are dry, grassy plains with few trees. Most of these grasslands have been turned into farmland. Farmers grow wheat and corn there.