Lake

A lake is a piece of water completely surrounded by land, 

Hills

Hills are land formations that are similar to mountains. Unlike mountains, however, hills are not peaked on top. Instead, hills have soft, rounded tops. They are made of grass, dirt, and rocks. 

Mountains

Mountains are large rock structures that are steep (rise quickly) and have pointed tops. 

Ocean

The salt water that covers much of the Earth's surface. 

River

A river is a large natural stream of water that flows over land.

Peninsula

A peninsula is land that sticks out into a body of water that is nearly surrounded by water. 

Plain

a plain is a large area of land with no hills or mountains. Plains mostly are more suitable for farming

Delta

a piece of land in the shape of a triangle or fan made by deposits of mud and sand at the mouth of a river.

Valley

Valleys are low areas between two mountains or hills. A valley can be large or small. It depends on the distance between the two mountains or hills.

Desert

Deserts are barren areas of the world that are very dry. They get very little rain, typically less than 10 inches of precipitation per year. Most think that deserts have to be hot, but some of the largest deserts in the world are cold.