Complex sentence: Aged 18 he scored his first goal during his full debut appearance on 28 July 1979, United's third goal in a 3--0 win over Dunfermline Athletic in a Drybrough Cup tie.
Split into simpler sentences: Aged 18 he scored his first goal during his full debut appearance on 28 July 1979. It was United's third goal in a 3--0 win over Dunfermline Athletic in a Drybrough Cup tie.