Complex sentence: Rochdale is a market town in Greater Manchester, England, positioned at the foothills of the South Pennines on the River Roch, north-northwest of Oldham, and north-northeast of the city of Manchester.
Split into simpler sentences: Rochdale is a market town in Greater Manchester, England. It lies at the foothills of the South Pennines on the River Roch, north-northwest of Oldham, and north-northeast of the city of Manchester.