Complex sentence: Littlehampton is a seaside resort with pleasure harbour town and the most populous civil parish in the Arun District of West Sussex, England, on the English Channel and east bank at the mouth of the River Arun.
Split into simpler sentences: Littlehampton is a seaside resort and pleasure harbour, and the most populous civil parish in the Arun District of West Sussex, England. It lies on the English Channel on the eastern bank of the mouth of the River Arun.