a dry, mostly flat grassland with few trees
prairie
a river or stream that flows into another river
tributary
a high river bank that stops the river from overflowing
levee
a part of a waterway that is closed off by gates
lock
A heavy snowstorm with strong winds
blizzard
is a piece of land given to someone to settle and farm there
homestead
land set aside by the United States government for Native Americans
reservation
In a factory, an arrangement where a product is moved from worker to worker, with each person performing a single task in the making of the product.
assembly line
Two explorers sent by the president to explore the Louisiana Purchase
Lewis and Clark
