Binhai College is quite modern. Every classroom for English study has a computer. Mr. Green often uses the computer to teach English. This makes his class more interesting. All the students like to use the computer. They do exercises on the computer. They also play word games on it. But this morning, something went wrong with the computer. It didn't work. Prof. Green and the students tried to get it fixed, but in vain. Mr. Green was very much troubled. The students were worried, too. Finally, they sent for a repairman. Now they are talking about the problems with the repairman.


Prof. Green:   What on earth is the matter with this computer? It
                      doesn't work.
Repairman:    Let me see. Oh, it's the virus.
Xiao Yong:     Virus! Does it cause damage to the system?
Repairman:    No, not that serious. But you have to send the
                      computer  to the service center.
            Lily:    Where does the virus come from?
Repairman:    You know, all of you use this computer, and many of
                      you bring in your floppies. You also receive e-mails
                      and e-mails sometimes carry viruses.
            Lily:     I see. How can you kill the virus and when will you get the computer fixed?
Repairman:    I hope it will be OK tomorrow.