Complex sentence: His mother, Katina (née Pappas; originally Panagiotopoulos), was of Greek descent, his father, Efthemios George Tsongas, was a Greek immigrant who worked as a dry-cleaner.
Split into simpler sentences: His mother, Katina (née Pappas; originally Panagiotopoulos), was of Greek descent. His father, Efthemios George Tsongas, was a Greek immigrant who worked as a dry-cleaner.