Simplify the following text for a Grade 8 native English-speaking person.
Original: In 1908 he joined the Conradh na Gaeilge ( the Gaelic League ) , where he Dubhghlas de hÃ de , later first President of Ireland , and also SinÃ ad Flanagan , another teacher who he married on 8 January 1910 at St Paul 's Church , Arran Quay , Dublin .
Simplified: In 1908 he joined the Ã rdchraobh of Conradh na Gaeilge ( the Gaelic League ) , where he met SinÃ ad Flanagan , a teacher by profession , and four years his senior . They were married on 8 January 1910 at St Paul 's Church , Arran Quay , Dublin .