Enter the past tense

"While at Purdue University on an NROTC scholarship in 1971, Roland Haas was recruited to become a deep cover CIA operative. He underwent intensive training to prepare for insertion into hostile areas, including High Altitude Low Opening (HALO) parachuting and weapons instruction. In the course of his first mission, which spanned Turkey, Iran, Afghanistan, and the former Soviet East Bloc, he assassinated several international drug dealers. In the middle of his mission Haas was thrown into an Iranian prison, where he was physically and psychologically tortured. Over the next thirty years he ...