【答案解析】As can be seen from the chart, great changes have been taking place in the ownership of mobile phones in China. At the end of 2002, there were 20 million mobile users. By the year 2005, the number will reach up to 30 million. People have found mobile phones very convenient. They can get in touch with each other whenever and wherever they like. There are many different functions for different needs, such as sending short messages and surfing the Internet. However, it may also bring us some trouble. For example, you will have to pay for a wrong number, and the radiation from the phone may do harm to our health. In spite of this, the number of people having mobile phones is still increasing steadily.