Complex sentence: Hucknall's Tesco superstore open in 2003 which created a number of jobs for the town in 2008 the store was extended to make it a Tesco Extra store.
Split into simpler sentences: Hucknall's Tesco superstore open in 2003 which created a number of jobs for the town. And in 2008 the store was extended to make it a Tesco Extra store.