Complex sentence: Before his election to the U.S. Senate, Schumer served in the US House of Representatives from 1981 to 1999, representing New York's 16th congressional district, later redistricted to the 10th congressional district in 1983 and to the 9th congressional district in 1993.
Split into simpler sentences: Before his election to the U.S. Senate, Schumer served in the United States House of Representatives from 1981 to 1999. He represented New York's 16th congressional district, which was later redistricted to the 10th congressional district in 1983 and to the 9th congressional district in 1993.