Complex sentence: David has been published by the South African newspaper "Mail & Guardian" and spoke on a panel of some of the most powerful people in South African radio at Africa's first international radio conference, RadioCon Africa 2004.
Split into simpler sentences: David has been published by the South African newspaper, the Mail & Guardian. He has also spoken on a panel of some of the most powerful people in South African radio at Africa's first international radio conference, RadioCon Africa 2004.