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　　Conversation A

　　Cam, a Canadian student, and his friend Megan are shopping for groceries.

　　Megan: What should we buy for tonight's barbecue?

　　Cam: Sausages, hamburgers, steaks ...

　　Megan: What are you, a caveman? Since when does a balanced diet consist of meat only?

　　Cam: OK, we can get onions, peppers, and corn.

　　Megan: That's better. Oh, I almost forgot about dried tofu.

　　Cam: Tofu? Who's going to eat that?

　　Megan: Don't knock it till you've tried it, caveman. You should try some local food for a change.

　　Cam: All right, I'll try it. But I still want my steak!

　　Conversation B

　　Megan: Do you know anything about food preparation?

　　Cam: What's there to know? You grab a steak, throw it on, and let it cook.

　　Megan: That casual attitude can lead to problems. Poor barbecuing techniques create cancer-causing chemicals in meat.

　　Cam: Cancer? That's not something we want on our menu!

　　Megan: No, it isn't. Those chemicals form when meat is exposed to intense heat. To avoid that, we should cook the meat at a lower temperature.

　　Cam: Would it help if we precooked it in the microwave?

　　Megan: It would, but the meat has to go onto the grill immediately after.

　　Cam: And we can't do that since we're going to the park.