阅读理解。 E-book is short for electronic (电子的) book. It is usually read on personal computers. Some mobile phones can also be used to read e-books. Earlier e-books were written for a specific group of readers and were about only a few subjects. With the development of the internet, knowledge and answers to a lot of questions mainly come from e-books. This is why the e-book business is increasing quickly. E-books have many advantages. First, they save time. We don't need to go to a bookstore to buy books, besides, we can find the topic we want to know about on the Internet, and then we can quickly get many e-books on similar topics. Second, e-books save money. Some e-books cost a little money, and there are millions of e-books on the Internet that we can get for free. Third, more trees are saved because e-books don't need to be printed(印刷) on paper. Fourth, e-books make reading more convenient. You can carry a whole library of hundreds of books with you in a small computer or any e-book reader (电子阅读器) without worrying about their weight. But e-books have certain disadvantages. They need a personal computer or an e-book reader and the information can be lost if its file format (文件格式) is not supported or changed in the reader's computer. However, e-books provide us with a new way of reading. That is good. 1. Why is the e-book business increasing quickly? Because _____. A. earlier e-books are about only a few subjects. B. people don't like to read any paper books any more. C. most e-books have been written for a specific group of readers. D. the development of the Internet makes e-books more useful. 2. How many advantages do e-books have according to this article? A. Three B. Four C. Five D. Six 3. Which of the following is true according to this article? A. E-books can't be red on mobile phones. B. All the e-books on the Internet cost lots of money. C. E-books can make reading more convenient. D. You can't read e-books without a personal computer. 4. What is the disadvantage of the e-books? A. You'll lose the information if its file format is not supported. B. You can carry hundreds of books in an e-book reader. C. You can buy cheap e-books anywhere. D. You can read e-books at any time. 5. The author mainly tells us _____. A. you don't need to buy paper books in a bookstore if you read e-books. B. the information can be lost if its file format is changed. C. the development of e-books can help save the environment.