Complex sentence: He has attempted to qualify for seven different Indy 500 races but only succeeded once, in his second attempt in 1996, his career not being helped by numerous arrests and convictions for driving while intoxicated.
Split into simpler sentences: He has attempted to qualify for seven different Indy 500 races but only succeeded once, in his second attempt in 1996. His career was affected by by numerous arrests and convictions for driving while intoxicated.