Complex sentence: He served in the United States House of Representatives from 1939 to 1947 and 1951 to 1954, and also in the U.S. Senate from 1954 to 1957.
Split into simpler sentences: He served in the United States House of Representatives from 1939 to 1947 and 1951 to 1954. He also served in the U.S. Senate from 1954 to 1957.