Complex sentence: In 1979, she released'Suspended Animation' on RCA, which was to be her last album for almost 20 years, as she mostly retired from live performance and instead focused on songwriting and production.
Split into simpler sentences: In 1979, she released'Suspended Animation' on RCA. That was to be Sands' last album for almost 20 years, as she mostly retired from live performance and instead focused on songwriting and production.