Complex sentence: In 1932, Robin went out to Hollywood to work for Paramount Pictures, and he and fellow composer Ralph Rainger became the leading film songwriting duo of the 1930s and early 1940s, with over 50 hits.
Split into simpler sentences: In 1932, Robin went out to Hollywood to work for Paramount Pictures. His principal collaborator was composer Ralph Rainger, together they became one of the leading film songwriting duos of the 1930s and early 1940s, writing over 50 hits.