Complex sentence: Riley was appointed Director General and Master of the Royal Armouries, Britain's national collection of arms and armour, early in September 2009, but resigned in order to have treatment for cancer in November 2012.
Split into simpler sentences: Riley was appointed Director General and Master of the Royal Armouries, Britain's national collection of arms and armour, early in September 2009. He resigned in order to have treatment for cancer in November 2012.