Complex sentence: Editions of "Beyond Our Ken" and "Round the Horne" are regularly broadcast on the digital radio service BBC 4 Extra and by 2006 over half a million copies of tapes and CDs of "Round the Horne" had been sold by the BBC.
Split into simpler sentences: Editions of "Beyond Our Ken" and "Round the Horne" are regularly broadcast on the digital radio service BBC 4 Extra. By 2006 over half a million copies of tapes and CDs of "Round the Horne" had been sold by the BBC.