Complex sentence: Marine Helicopter Squadron One (HMX-1), "The Nighthawks" based at Marine Corps Air Facility Quantico, Virginia, is responsible for the helicopter transportation of the President of the United States, Vice President, Cabinet members and VIPs.
Split into simpler sentences: Marine Helicopter Squadron One (HMX-1), is a United States Marine Corps helicopter squadron based at Marine Corps Air Facility Quantico, Virginia. Nicknamed "The Nighthawks," they are responsible for the helicopter transportation of the President of the United States, Vice President, Cabinet members and VIPs.