The writer thought that she understood.
A. Japanese subway etiquette
B. the Tokyo subway system
One thing that she did not understand was .
A. how to use her cell phone
B. when it is OK to use a cell phone on the subway
The other passengers looked at her when she.
A. had a conversation on her cell phone
B. tried to speak Japanese
When Japanese people use their cell phones on the subway, they are.
A. having long conversations with their friends
B. text messaging or playing games
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