Complex sentence: Ross enlisted in the United States Air Force at age 19 after graduating from Orlando High School, the Air Force transferred him to Eielson Air Force Base (in Alaska), where he first saw the snow and mountains that later became recurring themes in his artwork.
Split into simpler sentences: Ross enlisted in the United States Air Force at age 19 after graduating from Orlando High School. The Air Force transferred him to Eielson Air Force Base (in Alaska), where he first saw the snow and mountains that later became recurring themes in his artwork.