Don't you think your schoolbag is too heavy to bear? The e-schoolbag will free you from the weight. It is said that e-schoolbags are going to be brought into use in Chinese middle schools soon. An experiment with several hundred e-schoolbags will begin in seven cities: Beijing, Shanghai, Dalian, Shenzhen, Chongqing, Taiyuan and Shijiazhuang. And the e-schoolbags are going to cover all over China if the experiment proves to be successful. In fact, the e-schoolbag should perhaps be called an e-notebook. It is a small hand-held computer for school students. Heavy schoolbags have long been a serious problem for school students. The average schoolbag of middle school students weighs up to 5 kilos. But the e-schoolbag will change everything. It is much lighter than a usual schoolbag, weighing under 1 kilo. Also, it is no bigger than a usual book, but it can still hold all the things for study, such as a textbook, a notebook and exercise book. They could be made into chips that are as small as a stamp. The students can read the text page by page on the screen. They can still take notes using a special electronic pen. If they want to know the meaning or the pronunciation of a new word, or even e-mail their teachers, it's just a press of a button. In some foreign countries, it is becoming common. But it is hard to tell when people will receive this new form of study. Some say that e-textbooks can be easily broken, some say that it is not good to students' eyesight to look at the screen for long.  But only time will tell. According to the passage, the e-schoolbag    _   .
is not heavy as before but still large is used as an experiment in Tianjin is made of metal is going to cover China if it proves to be successful