Complex sentence: In 1978, Iwasaki became frustrated with the tradition-bound world of the geiko, particularly what she saw as inadequacies in the education system, and unexpectedly retired at the height of her career, aged just 29.
Split into simpler sentences: In 1978, Iwasaki became frustrated with the tradition-bound world of the geiko. Iwaski unexpectedly retired at the height of her career, aged just 29.