Complex sentence: Allerton Hall was purchased by John and James Hardman in 1736, John later became a mp in 1754.before it was owned by William Roscoe between 1798 and 1813.
Split into simpler sentences: Allerton Hall was purchased by John and James Hardman in 1736, John later became a MP in 1754. Before this, it was owned by William Roscoe between 1798 and 1813.