Complex sentence: Vasubandhu was a philosopher who wrote on the Abhidharma from the perspectives of the Sarvastivada and Sautrāntika schools and, along with his half-brother Asanga, he was also one of the main founders of the Yogacara school after his conversion to Mahayana Buddhism.
Split into simpler sentences: Vasubandhu was a philosopher who wrote on the Abhidharma from the perspectives of the Sarvastivada and Sautrāntika schools. Along with his half-brother Asanga, he was also one of the main founders of the Yogacara school after his conversion to Mahayana Buddhism.