Complex sentence: She had earlier been elected by the National University of Ireland to Seanad Éireann, where she sat as an independent senator from 1977 until 1980, before serving as Fine Gael spokesman on Women's Affairs and then (1981--1982) Government Leader of the Seanad.
Split into simpler sentences: She had earlier been elected by the National University of Ireland to Seanad Éireann, serving in the upper house of the Oireachtas from 1977 until 1982. She sat as an independent senator for the first three years, before serving as Fine Gael spokesman on Women's Affairs (1981--1982) and then Government Leader of the Seanad.