Complex sentence: Edison is on the east side of Raritan Valley (a line of communities in central New Jersey), along with Plainfield, and completely surrounds the borough of Metuchen, New Jersey.
Split into simpler sentences: Edison is on the east side of Raritan Valley (a line of communities in central New Jersey), along with Plainfield, and completely surrounds Metuchen. Edison completely surrounds the borough of Metuchen, New Jersey.