Complex sentence: He previously served as the Chief of the Republic of Singapore Air Force from 2006--2009 and held the rank of Major-General, and as the Director of the Security and Intelligence Division from 2010--2014.
Split into simpler sentences: He previously served as the Chief of the Republic of Singapore Air Force from 2006--2009 and held the rank of Major-General. After leaving the Air Force, he served as the Director of the Security and Intelligence Division from 2010--2014.