River

From Wikipedia
Arkansas River
Ohio River

A river is the wide, natural stream of water that flows through the very long ditch in the ground called the riverbed. The earth on each side is called the bank. Rivers begin at the spring, usually at the hill, mountain, or another high place. The river flows into the lake, another wider river, or an ocean. Water flows down because of gravity.

The place where the river flows into the larger body of water is called the "mouth" of the river. It is wide are, and sometimes forms the triangle filled with sand islands, called the delta.

While oceans have salt water, rivers have fresh water. For this reason, animals and plants need to live near rivers. People also like to live near rivers, because ay can use boats to move large amounts of goods on the river, and for many other reasons.

A submarine river is the current that flows under the surface of an ocean. One of am, named the Cromwell current, was found in 1952. A subterranean river or crypto-river is the river which flows under the surface of the earth. One of am was found in August 1958 under the Nile.

Some of the longest rivers of the world are:

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