Complex sentence: The 1939 U.S. Open was the 43rd U.S. Open, held June 8--12 at Philadelphia Country Club in Gladwyne, Pennsylvania, a suburb northwest of Philadelphia.
Split into simpler sentences: The 1939 U.S. Open was the 43rd U.S. Open. The golf tournament was held June 8--12,1939 at Philadelphia Country Club in Gladwyne, Pennsylvania, a suburb northwest of Philadelphia.