Simplify the following text for a Grade 4 native English-speaking person.
Original: Two of the fifty largest cities in the United States are located in Oklahoma , Oklahoma City and Tulsa , and 58 percent of Oklahomans live within their metropolitan areas , or spheres of economic and social influence defined by the United States Census Bureau as a metropolitan statistical area .
Simplified: Two of the fifty largest cities in the United States are in Oklahoma . They are Oklahoma City and Tulsa .