Complex sentence: The main site under excavation was a 4th-century vessel 19 metres in length, lying between 36 and 42 metres below the sea surface 100 metres south of Yassi Ada.
Split into simpler sentences: The main site under excavation was a 4th-century vessel 19 metres in length. It lies between 36 and 42 metres below the sea surface and is 100 metres south of Yassi Ada.