Complex sentence: He soon after won his first chair at the Llanddewi Brefi eisteddfod in 1913 at the age of 17, in addition to three others at eisteddfodau in Tregaron, Ysbyty Ystwyth and Rhydcymerau before he was 25 years of age.
Split into simpler sentences: He soon after won his first chair at the Llanddewi Brefi eisteddfod in 1913 at the age of 17. He later won three additional chairs at eisteddfodau in Tregaron, Ysbyty Ystwyth and Rhydcymerau before he was 25 years of age.