Complex sentence: On May 7,1949, Arnold was honored by being made the first and to date only General of the Air Force, being the only American to serve in five-star rank in two of its military services.
Split into simpler sentences: On May 7,1949, Arnold was honored by being made the first, and to date only, General of the Air Force. He is the only American to serve in a five-star rank in two of its military services.