听力原文：W: Hi, John! M: Oh! Hi, Laura! What are you doing here? W: Uh, I'm usually here on weekends. It's my dad's shop. So you are looking for a bike? M: Yeah. Now that the weather is warming up, I think I should get some exercise instead of taking the bus all the time. W: Well, you come to the right place. What would you like? M: Well, I don't want a racer or a touring bike or anything. Mostly I'll just use it to get me back and forth from work. W: How far is that? M: About four miles. W: Are there a lot of hills on the way? M: Some. But maybe I should tell you at first that I only have 150 dollars. Can I get anything decent for that? W: Well, you are not going to get anything top of the line. But we do have a few trade-ins in the back that are in good condition. M: That sounds good. W: And you are right. For the kind of ride you are going to be doing, the most important thing is comfort. You'd better make sure it's the right height for you. Follow me and I'll show you what we've got. Why is Laura at the bicycle shop?