450)=450"> 450)=450"> 每天18：00准时更新 [color=#408080]HINTS The Dewey Melvil Dewey [/color] 全文听写，英式拼法 订阅节目更方便
All libraries have a system for organizing and classifying nonfiction books. The most widely used system is The Dewey decimal system. It was designed by an American librarian named Melvil Dewey. It is called a decimal system because it divides all nonfiction books into ten major categories. These are further divided into subdivisions. For example, all science books are numbered from 500 through 599. Each different field of science has a number within the 500 category. For example, astronomy is 520, and chemistry is 540. The Dewey decimal system provides a category for every type of nonfiction book. The best way to locate a book in the library is to use the card catalog. The card catalog is an index of all the books in the library. Information about a book is listed on cards. All the cards are filed alphabetically and stored in drawers in large cabinets. The card catalog can help you locate a particular book, a book on a certain subject, or a book by a particular author. In the card catalog, each book has three cards, an author card, a title card and a subject card. The author card is alphabetized under the author's name The title card is filed alphabetically according to the title of the book. The subject card is filed alphabetically under the name of the subject of the book.