You look for a book in one of two ways： /either you’ll know the author and title of the book, / or else you  want a book on a particular subject. / Let’s start with what to do if you know the author’s name and the title of the book. / The first thing is to look up the author’s name in the Author Catalogue. / If you can find a card for the book, / you should then write down three things： / the author, the title and the class number. / Now find the class number on the library shelves. / There are notices on the bookcases called shelf guides. / If you find the book on the shelf, / and you want to borrow it, take it to the Issue Desk. / You should ask the librarian to reserve it for you.