Complex sentence: He took over "The Radio 1 Breakfast Show" on Monday 5 January 1981, a spot notable for his on-air decision in 1984 not to play the Frankie Goes to Hollywood single "Relax" due to supposedly obscene lyrics.
Split into simpler sentences: He took over "The Radio 1 Breakfast Show" on Monday 5 January 1981. In 1984 he made an on-air decision in 1984 to interrupt broadcasting the Frankie Goes to Hollywood song "Relax" owing to its supposedly obscene lyrics.