If it is not serious, it can still be returned to the library after drying and flattening. If the book is seriously damaged, you can only compensate. You can buy the same book to compensate the library, and the library will charge a small processing fee. If you can't buy the same book, you can only lose money according to the regulations of the library. The library has relevant regulations on compensation for all kinds of books, which is about 3-30 times, so it is best to compensate books as much as possible.