Complex sentence: However, the U.S. Department of Defense does not recognize this date since the men were supposedly only training the Vietnamese, so the officially recognized date is the formation of the Military Assistance Command Viet-Nam, better known as MACV.
Split into simpler sentences: However, the U.S. Department of Defense does not recognize such date since the men were supposedly only training the Vietnamese. The officially recognized date is the formation of the Military Assistance Command Viet-Nam, better known as MACV.