Complex sentence: His widow, Mrs Gundula Holbrook, donated his medal to the Council of the Shire of Holbrook in 1982 and subsequently made a substantial donation to the establishment of a submariners' memorial in the town in 1995 and in 1997 visited the town to unveil it.
Split into simpler sentences: His widow, Mrs Gundula Holbrook, donated his medal to the Council of the Shire of Holbrook in 1982. In 1995 she made a substantial donation towards the establishment of a submariners' memorial in the town and in 1997 visited the town to unveil it.