Complex sentence: Wilson's first public appearance as a singer was in Vaughan Williams's incidental music for Aristophanes' "The Wasps" in 1909, and he made his first appearance in opera as Tamino in Mozart's "The Magic Flute" in 1911.
Split into simpler sentences: Wilson's first public appearance as a singer was in Vaughan Williams's incidental music for Aristophanes' "The Wasps" in 1909. He made his first appearance in opera as Tamino in Mozart's "The Magic Flute" in 1911.