Answer
Tress MacNeille has been working on the animated series The Simpsons since 1999. She has voiced many characters on the show, including Marge Simpson, Patty and Selma Bouvier, Jacqueline Bouvier-Terwilliger, Helen Lovejoy, Maude Flanders, Agnes Skinner, Mrs. Krabappel, and many others. She is one of the most prolific voice actresses in the industry, and her work on The Simpsons has made her a household name.