阅读下面这首唐诗，完成文后各题。

早雁①

杜牧

金河②秋半虏弦开，云外惊飞四散哀。

仙掌③月明孤影过，长门④灯暗数声来。

须知胡骑纷纷在，岂逐春风一一回。

莫厌潇湘少人处，水乡菰③米岸莓苔。

【注释】①唐武宗会昌二年（842年）八月，北方回鹘族乌介可汗率兵南侵，引起边民纷纷逃亡。杜牧时任黄州（今湖北黄冈）刺史，闻此而忧之，因写下此诗。②金河，在今内蒙呼和浩特市南。③仙掌：指长安建章宫内铜铸仙人举掌托起承露盘。长门，汉宫名。

A : What's your favourite invention?

B : Of course computers. They are very important in people's life now.       

A: I like computers, too. I think they will be used even more widely in the future.

B: I agree with you.        

A: I usually use my computer for looking up information reading books and playing games;

B: Do you like shopping online?

A : Yes, of course.       

B: That's true. However, sometimes it isn't safe to buy things online.

A: Yes, so we should be careful when shopping online. What do you like to do with your computer?

B:        

A: You must have many net friends.

B: Sure. I have about 10 friends who are from different countries.

A:        

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