Complex sentence: Later, he taught at Galatasaray High School, where one of his students was Fikret Muallâ Saygı, who would later become one of Turkey's first avant-garde painters.
Split into simpler sentences: Later, he taught at Galatasaray High School. One of his students there was Fikret Muallâ Saygı, who would later be among Turkey's first avant-garde painters.