Complex sentence: SFGC was founded by Elizabeth Appling, who served as the organization's Artistic Director until her retirement in 1992 and was succeeded by Sharon J. Paul, who led the chorus until just after its 21st anniversary in 2000.
Split into simpler sentences: SFGC was founded by Elizabeth Appling, who served as the organization's Artistic Director until her retirement in 1992. She was succeeded by Sharon J. Paul, who led the chorus until just after its 21st Anniversary in 2000.