Simplify the following text for a Grade 8 native English-speaking person.
Original: Of these settlements above , South Yorkshire has three main urban areas : the Dearne Valley which covers Barnsley and surrounding area ; the Sheffield urban area which covers Sheffield , Rotherham and surrounding area ; and the Doncaster urban area which covers Doncaster and surrounding area .
Simplified: Dearne Valley is made up of Barnsley and a number of villages and towns . The Sheffield urban area is made up of Sheffield and Rotherham and the Doncaster urban area is Doncaster and surrounding areas .