Complex sentence: In 1981, Sixx founded Mötley Crüe with drummer Tommy Lee, later being joined by guitarist Mick Mars through an ad in the local newspaper he was reading, then by singer Vince Neil with whom Tommy had attended high school.
Split into simpler sentences: In 1981, Sixx founded Mötley Crüe with drummer Tommy Lee. They were later joined by guitarist Mick Mars through an ad in the local newspaper, and singer Vince Neil with whom Tommy had attended high school.