Complex sentence: Having served on combat operations both in Iraq and Afghanistan, Brock left the British Army so that he could start his career in the motion picture industry-it was at this time that he adopted the stage name'Brock'.
Split into simpler sentences: Having served on combat operations both in Iraq and Afghanistan, Brock left the British Army so that he could start his career in the motion picture industry. It was at this time that he adopted the stage name'Brock'.