Complex sentence: Gerald lost his vision completely in 1981 due to a failed cataract operation, however he contributed his time and energy to the Sri Lanka Council for the Blind, whilst his wife Dulcie continued to look after the interests of Sooriya.
Split into simpler sentences: Gerald lost his vision completely in 1981 due to a failed cataract operation. He contributed to the Sri Lanka Council for the Blind, while his wife Dulcie continued to look after the interests of Sooriya.