Mr Smith had a week holidays, so he said, “I'm going to see the sea by train．”He put on his best clothes, took a small bag, went to the railway station and got into the train．He had a beautiful hat, and he often put his head out of the window during the trip and looked at the beautiful scenery(景色)．But the wind pulled his hat off．Mr Smith quickly took his old bag and threw it out of the window, too．The other people in the train laughed, “Is your bag going to bring back your beautiful hat?”they asked．“No, ”Mr Smith answered．“But there is no name and no address on my hat, and there's a name and an address on the bag．If someone finds both of them, he or she will send me the bag and hat．”Why did Mr Smith throw his old bag out of the window?Because ________．

“I sometimes get up at three or four in the morning and I surf the net．”“I often check my e-mail forty times a day．”“I often spend more than three hours during one time on the net．”“I spend more time in Chat Rooms than with my‘real-life’friends．”Do you know any people like these?They are part of a new addiction(瘾)called Internet addiction．Internet addicts spend at least thirty to forty hours online every week．The use of the Internet can be an addiction like drug(毒品)use．People lose control of the time they spend on the Internet．For example, one college student was missing for several days．His friends were worried, and they called the police．The police found the student in the computer lab：he was surfing the net for several days straight．Studies show that about 6％ to 10％of Internet users become addicted．And people worry about the teens because the Internet is changing the playing field for some of them．They spend more time in cyberspace than in the real world of friends and family．Is“surfing the net”a hobby or an addiction for you?You may have a problem if you have these symptoms(症状)：---You don't go to important family activities or you do not do school work because you like to spend hours on the Internet．---You can't wait for your next online time．---You plan to spend a short time online, but then you spend several hours．---You go out with your friends less and less．What is the writer trying to tell us at the end of the passage?