Complex sentence: Pottinger joined the Marine Corps as an military intelligence officer in September 2005 and served three deployments: one in Iraq from April to November 2007 and two in Afghanistan from November 2008 to May 2009 and July 2009 until May 2010.
Split into simpler sentences: Pottinger joined the Marine Corps as an military intelligence officer in September 2005. He served three deployments: one in Iraq from April to November 2007 and two in Afghanistan from November 2008 to May 2009 and July 2009 until May 2010.