Complex sentence: With his wife Dorothy, whom he met at the MacDowell Colony in 1922, he was co-author of the non-musical play adapted from the novel, which became the foundation of George Gershwin's opera "Porgy and Bess".
Split into simpler sentences: With his wife Dorothy, whom he met at the MacDowell Colony in 1922, he was co-author of the non-musical play adapted from the novel. His play was the foundation of George Gershwin's opera "Porgy and Bess".