After I made it to the city center, I started to feel it might be easy for a foreigner to deal with the great size of Beijing. With growing confidence, I decided to take the subway to the hotel, not realizing that the network didn't go that far. Impressed with the cleanliness of the station, I bought a ticket and boarded the first train that came along. After a few minutes I asked in English of course a young man seated next to me where I should get off closest to the Friendship Hotel. Wearing a smart business suit and tie, he would surely speak English, wouldn't he? Unfortunately, he couldn't understand me but seemed very friendly. I showed him the room card with all the information of the Friendship Hotel in Chinese characters. He looked at it, and then his eyes moved quickly to the carriage   subway map. Next, he raised three fingers of his right hand. In Australia, raising fingers at someone is not usually nice, but this man wasn't smiling. At the next station he showed me two fingers. Now in   Australia, that's really rude, but I got the message. When we stopped at the third station, he didn't just point to the door, but got up, took me out of the train, and led me to the top of the stairs, and out onto the street. Then he stopped a taxi and told the driver where to take me. All this came from a man who couldn't speak my language, and I couldn't speak his. I was now speechless, especially when he refused my offer of money. I felt a little embarrassed having even thought he would accept a tip. This experience made it clear I had to learn some Chinese quickly or my adventures might start turning into bad luck. The author's purpose of writing this passage is mainly to   _  .
prove the importance of being careful appreciate the kindness of the young man complain some cultural misunderstanding describe one of his adventurous experiences