Complex sentence: On the last day of December 1759 Arthur Guinness rode through the gate of the dilapidated brewery-having signed a lease on the property for 9,000 years at £45 per annum.
Split into simpler sentences: On the last day of December 1759 Arthur Guinness rode through the gate of the dilapidated brewery. He had just signed a lease on the property for 9,000 years at £45 per annum.