阅读理解。 Mapping China online If you want to check where the nearest coffee shop to your home is,if you want to know how to get to a scenic spot(景点)  in your city,or if you want to see where in the world your foreign pen friend lives, there's now a new free online map you can use. Last month,China started its official online mapping service,Map World.  'The free online service will allow users to fly over mountains and plains around the world and search restaurants and traffic information across the country,free of charge,' said Xu Deming,director of the State Bureau of Surveying and Mapping(SBSM).  The bureau,which does China's surveying and mapping work,is in charge of the Map World project. Users can enter Map World through www. tianditu. cn or www. chinaonmap. cn and search for two-and three-dimensional(维) images(图像) from across the world. The home page shows a view of the Great Wall. 'It took about two years to prepare the service with all the satellite images taken from 2006 to 2010, ' said Jiang Jie,director of the database(数据库)  department under SBSM. The technology and website are still at an early stage. The images from inside China are detailed. Users can see close pictures of roadsides. But the views of places outside China are less clear. Service providers have more than 80 machines,with the ability to handle(处理) 10 million requests daily,while Google Earth,Google's mapping service,has thousands of machines,Jiang said. 'Our map service can update data about twice a year,but Coogle Earth can update its information every couple of minutes,through satellites,' Jiang said. The bureau said it would continue developing Map World. Meanwhile,you can have a try for yourself. Some users have given positive feedback(反馈) after trying the service. One student in Beijing told teens that Map World even showed the small bookstore near her school. 1. What is the main function of the first paragraph? A. To show how valuable the service is. B. To introduce the new online photo-map of China. C. To show the importance of the new online photo-map. D. To tell how popular the new online photo-map is.in China. 2. The underlined word 'detailed' in Paragraph 5 is closest in meaning to ______ A. exact B. large C. complete D. valuable 3. According to the bureau,Map World ______. A. only has images of China B. will need another two years to complete C. needs further development D. begins with the Great Wall 4. What disadvantages does Map World have,compared with Google Earth? A. Information is updated much less frequently. B.  It provides less clear images of places in China. C. Its machines are less high tech. D. It only has black and white images.