One summer, library in Texas in the United States was having a terrible problem. It had grown too big for its building and had to move to a newly-built library across town. Everything was finished and paid for, the librarians(图书馆人员) found out that they hadn’t left enough money to move their mountains of books across the town. Even the cheapest moving company was going to ask several hundred thousand dollars to pack and move the books. What could they do? Finally one clever librarian had a bright idea. She said the move was going t o take all summer and during that time, the library would be closed. Why not ask everyone to come in to borrow 20,40,or 100 books? At the end of the summer they could return them—to the new library. The idea worked beautifully and not only did the library save a lot of money. but also people read a lot of books.