Complex sentence: Wilson, Keppel and Betty were a popular British music hall act in the middle decades of the 20th century who capitalised on the trend for Egyptian imagery following the discovery of the tomb of Tutankhamun.
Split into simpler sentences: Wilson, Keppel and Betty formed a popular British music hall act in the middle decades of the 20th century. They capitalised on the fashion for Ancient Egyptian imagery following the discovery of the tomb of Tutankhamun.