dunce

1. N-COUNT If you say that someone is a dunce, you think they are stupid because they find it difficult or impossible to learn what someone is trying to teach them. 笨学生[表不满]

Michael may have been a dunce at mathematics, but he was gifted at languages. 迈克尔在数学方面可能是个笨学生，但他在语言方面是有天赋的。