Complex sentence: In 1947, Pettit joined the faculty of Stanford University; he was named Professor of Electrical Engineering in 1954, and became Dean of the Stanford School of Engineering in 1958, a post which he held until 1972.
Split into simpler sentences: In 1947, Pettit joined the faculty of Stanford University, and was named Professor of Electrical Engineering in 1954. He was named Dean of the Stanford School of Engineering in 1958, and would remain in the position until 1972.