Complex sentence: West Palm Beach, is a city located on the Atlantic coast in southeastern Florida and is the most populous city in and county seat of Palm Beach County, the third most populous county in Florida with a 2010 population of 1,320,134.
Split into simpler sentences: West Palm Beach, is a city located on the Atlantic coast in southeastern Florida. It is the is the county seat of Palm Beach County, the third most populous county in Florida with a 2010 population of 1,320,134.