Complex sentence: The 1961 U.S. Open was the 61st U.S. Open, held June 15--17 at Oakland Hills Country Club in Birmingham, Michigan, a suburb north of Detroit.
Split into simpler sentences: The 1961 U.S. Open was the 61st U.S. Open. The golf tournament was held June 15--17,1961, at Oakland Hills Country Club in Birmingham, Michigan, a suburb north of Detroit.