Complex sentence: He left Illinois for Columbia University, where he taught from 1919 until 1958: he was a member of Columbia's English faculty and held an emeritus position there from 1958 until his death in 1966.
Split into simpler sentences: He left Illinois for Columbia University, where he taught from 1919 until 1958. He was a member of Columbia's English faculty and held an emeritus position from 1958 until his death in 1966.