answer: John meets Benjamin. Benjamin feels bad because of the jet lag, then they begin to talk about the knowledge of China, including the Grea Wall and Chinese tea.
documents: #Person1#: Hi, I'm Benjamin. Nice to meet you here. You look great. 
  #Person2#: Thank you. Nice to meet you too. I'm John. Is this your first time to take a long-distance trip on plane. 
  #Person1#: No, this is the second time. But I also feel bad because of the lower pressure and the jet lag. 
  #Person2#: Oh, I am sorry to hear that. Take it easy. It will be OK soon. You see, I take this long-hour plane frequently, but the jet lag still makes me uneasy. 
  #Person1#: Oh, that's too bad. Do you get a good knowledge of China? 
  #Person2#: Yes, whenever I think about China, I'd see the Tian'an Men Square. China is a very beautiful country. And I've seen many landmarks in China but I like the Great Wall most. 
  #Person1#: All of the Chinese are proud of the Great Wall. And it was built before the Qin dynasty near Shan Haiguan-the First Pass in the World. 
  #Person2#: Was it built before the Qin dynasty? I thought it was in the Ming dynasty. 
  #Person1#: No, before the Qin dynasty. 
  #Person2#: Oh, yeah. Thought I am an American, I know quite a lot about China and I like Chinese tea very well. 
  #Person1#: Both the green tea and the black tea are good for our health. And I usually refresh myself with a cup of tea.