Complex sentence: In 1942, Claude Delvincourt, director of the Paris Conservatoire, reopens the saxophone class since the departure of Adolphe Sax in 1870, and decided to entrust the post of professor of saxophone to Marcel Mule, then 41 years and very respected in France and abroad.
Split into simpler sentences: In 1942, Claude Delvincourt, director of the Paris Conservatoire, allowed for the reestablishment of the saxophone studio, which had been abandoned with the departure of Adolphe Sax in 1870. Delvincourt entrusted the post of professor of saxophone to Marcel Mule, who was 41 years of age, and highly respected in France and abroad.