7.聽下面一段材料,回答第18至20題. 18.What kind of book can be taken out of the library? A.A dictionary. B.A novel. C.A magazine. 19.How long can you keep the book? A.For a week. B.For two weeks. C.For three weeks. 20.Where can you borrow science books? A.In the first room. B.In the second room. C.In the third room.