听力原文：M: Hello. I need to talk with someone about my driver's license. W: Yes. How may I help you? Do you have a driver's license, or do you need to get one? M: Well, I'm not sure. You see, I have an international driver's license. W: Uhuh. And how long will you be staying in the United States? M: Probably four years, until I finish my degree. W: Oh. Then you will need to get in Arizona driver's license. M: Do I have to take a driver's test to do that? W: Yes, you do. You need to come in and take a written exam and an eye exam, and then you need to take a road test with a parallel parking test. Did you say that you are a student? M: Yes, I'm a student at the university. I don't have ID with me, but I can go get it. W: Okay. Then you can apply for a limited license. Just come back and show your student ID, and you can make application for a five-year Ii cease. M: Great. That's what I want. So I don't have to take the driver's test then. W: Oh, Yes you do. The license only costs you ten dollars. A regular license would cost you a lot more than that, but it is valid for more than five years. M: Why can't I just use my international driver's license? W: You could if you were just visiting not less than a year. But as a student, you will be temporarily residing in our state. M: Okay. So that's why my friend can use his international license, he is a tourist. W: Right. What is the main purpose of the conversation?