Complex sentence: Back at Jerry's Headquarters, a stern Jerry is responding to his friend's letter, answering: Dear Francois, it is with deep regret that I must inform you that your son will never make a mousketeer.
Split into simpler sentences: Back at Jerry's Headquarters, a stern Jerry is responding to his friend's letter, answering: Dear Francois. It is with deep regret that I must inform you that your son will never make a mousketeer.