Complex sentence: Her Naval Armed Guard crews earned "Battle Stars" for participating in the Assault-Occupation of Iwo Jima 25 Feb-6 March 1945 and the Battle of Okinawa and Occupation of Okinawa Gunto 27 May-4 June 1945.
Split into simpler sentences: Her Naval Armed Guard crews earned "Battle Stars" for participating in the Assault-Occupation of Iwo Jima from 25 Feb. to 6 March 1945. Also for the Battle of Okinawa and Occupation of Okinawa from 27 May to 4 June 1945.