Complex sentence: He also led a gospel group, The Seekers, in the 1970s, and returned to rockabilly music when he performed with the Sun Rhythm Section and worked again in the 1980s with Jerry Lee Lewis.
Split into simpler sentences: He also led a gospel group, the Seekers, in the 1970s. He returned to rockabilly when he performed with the Sun Rhythm Section and worked again in the 1980s with Jerry Lee Lewis.