Complex sentence: In late 1977 Orbison started feeling unwell and decided to take a holiday to Hawaii to rest, but while there he was admitted to hospital and tests revealed three of his coronary arteries were severely clogged.
Split into simpler sentences: In late 1977 Orbison started feeling unwell and decided to take a holiday in Hawaii to rest. While there he was admitted to hospital, and tests revealed three of his coronary arteries were severely clogged.