answer: #Person1# and #Person2# are talking about the top-ranking popular sport, ping-pong, in China. #Person2# thinks its critical advantage is the low cost because it just needs a racket, a table, and a ball. #Person1# adds that sometimes substitutes also work. #Person1# and #Person2# say that many leaders are good at it.
documents: #Person1#: Ping-pong must be the top-ranking popular sport in China. It seems to me in every school, factory, army unit, or residential area, men and women, young and old, are swinging paddles.
  #Person2#: You got it! In a sense, it has become a byword for Chinese sport.
  #Person1#: What do you think might be the source of its popularity?
  #Person2#: I think its critical advantage lies in its low cost. All you need is a racket, a table and a light celluloid ball. Tables are usually available in public recreation areas, like finest rooms, and outdoor playgrounds. . .
  #Person1#: And sometimes a substitute table can be made out of a few desks.
  #Person2#: Put it there! In senior high schools, we used to play on desks in the classroom, when no vacant tables were available. Likewise, the racket may take a variety of forms, too. Anything that resembles a racket, from a plank to cardboard or even a hardcover book, may be used as a racket.
  #Person1#: Haha, these are very good inventions. All these speak the public's fondness for the sport
  #Person2#: Yeah, the sport is affordable and accessible to every Tom, Dick and Jane in this developing country. No wonder even the state leaders are known to be keen on it.
  #Person1#: I know President Hu Into likes playing ping-pong.
  #Person2#: Actually, he excels in it. Chairman Mao, too, encouraged the whole nation to play ping-pong as a part of the nationwide body building campaign.
  #Person1#: I see. There was also the famous ping pong diplomacy, wasn't there?