Complex sentence: He was sent as a boarder to a Preparatory School in Clifton, Bristol, in the hope that he might be able to achieve entrance to a public school but after failing to gain a scholarship, he attended Cheltenham College for Boys as a day pupil.
Split into simpler sentences: He was sent as a boarder to a Preparatory School in Clifton, Bristol, in the hope that he might be able to achieve entrance to a public school. However, after failing to gain a scholarship, he attended Cheltenham College for Boys as a day pupil.