Complex sentence: But after that long retirement she published her masterpiece Wide Sargasso Sea in 1966 that Rhys emerged as a significant literary figure, with Wide Sargasso Sea she won the prestigious WH Smith Literary Award in 1967.
Split into simpler sentences: But after that long retirement she published her masterpiece, Wide Sargasso Sea, in 1966 that Rhys emerged as a significant literary figure. With Wide Sargasso Sea she won the prestigious WH Smith Literary Award in 1967.