It could be a number of possible answers. The book on a shelf; the book on the shelf; a book on a shelf; or a book on the shelf. Ukrainian isn't specific. Context might tell you which version would be the translated meaning. However, in Ukrainian it is 'book on shelf', as there is no definite or indefinite article. However, if you wanted to refer to a particular book, you would use 'це' to specify 'this book'.