confusing~~~~~~

when I talk with the other foreigners, I don't know what I shall say. Because we live different countries, we have different belief, I am always comfused to make a conversation. when I ask them questions, I want to avoid to concern about something of private. When I want to break off silent, I wonder if the topic is suitable. In recent day, some friends give me their phone number when we talk. however, I refuse to do this because I am not accustomed to give my phone no. to the person I have met for a short time. In a word, it is difficult to learn another language. not only have we learned the pronounce, spelling, grammer, we also have a knowlege of the country.