[originaltext] An idea that started in Seattle’s public library has spread t

An idea that started in Seattle’s public library has spread throughout America and beyond. The concept is simple: help to build a sense of community in a city by getting everyone to read the same book at the same time.
    In addition to encouraging reading as a pursuit to be enjoyed by all, the program allows strangers to communicate by discussing the book on the bus, as well as promoting reading as an experience to be shared in families and schools. The idea came from Seattle librarian Nancy Pearl who launched the "If All of Seattle Read the Same Book" project in 1998. Her original program used author visits, study guides and book discussion groups to bring people together with a book, but the idea has since expanded to many other American cities, and even to Hong Kong. In Chicago, the mayor appeared on television to announce the choice of To Kill a Mockingbird as the first book in the "One Book, One Chicago"program. As a result, reading clubs and neighborhood groups sprang up around the city. Across the US, stories emerged of parents and children reading to each other at night and strangers chatting away on the bus about plot and character.The only problem arose in New York, where local readers could not decide on one book to represent the huge and diverse population. This may show that the idea works best in medium-sized cities or large towns, where a greater sense of unity can be achieved.
    Ultimately, as Nancy points out, the level of success is not measured by how many people read a book, but by how many people are enriched by the process.
Questions 16 to 19 are based on the passage you have just heard.
16. What is the purpose of the project launched by Nancy?
17. Why was it difficult for New Yorkers to carry out the project?
18. According to the passage, where would the project be more easily carried out?
19. According to Nancy, what is the degree of success of the project judged by?