What is polar bear polar bear what do you hear?

"Polar Bear, Polar Bear, What Do You Hear?" is a children's picture book written by Bill Martin Jr., illustrated by Eric Carle, and published in 1991. The book is a follow-up to "Brown Bear, Brown Bear, What Do You See?" and features a similar repetitive structure. In the book, various animals introduce themselves and ask each other what they hear. The polar bear hears a walrus, a seal, and a narwhal. The book introduces children to different animals and the sounds they make, while also teaching them to recognize patterns and repetition in language. The book is popular with parents and educators for its engaging illustrations and language.