(Now many students have bought laptops, which is an extra way to pass the time in the boring college life. However, when they bring their laptops home during winter or summer vacations, they find that this machine can only be used for watching videos or playing stand-alone games. , Of course, some classmates are connected to the Internet at home, and some classmates who have a wealthy family can also buy a monthly wireless network card and enjoy it, but most of the classmates may not be like this.)