Complex sentence: Trinny and Susannah are Trinny Woodall and Susannah Constantine, are a well-known British double act who are best know for being fashion gurus and for presenting the BBC television series "What Not to Wear".
Split into simpler sentences: Trinny and Susannah are Trinny Woodall and Susannah Constantine, are a well-known British double act. They are best know for being fashion gurus and for presenting the BBC television series "What Not to Wear".