Complex sentence: He competed for the United States in the 1912 Summer Olympics held in Stockholm, Sweden in the standing high jump, where he won the gold medal, and in the standing long jump, where he won the silver medal.
Split into simpler sentences: He competed for the United States in the 1912 Summer Olympics held in Stockholm, Sweden in the standing high jump where he won the gold medal. He also competed in the standing long jump where he won the silver medal.