听力原文：M: We are having a debate on advertising Thursday evening, and I have to take part. W: That's interesting. I should like to hear what people think about advertising. M: What's there to say? We must have advertising, mustn't we? W: Why? M: Well, we wouldn't know what there was to buy if we didn't have advertisements. W: Yes, that's true. Up to a point, advertisements provide information that we need. If someone has produced a new article, naturally, the seller wants to tell us about it. M: Yes, and the advertisements tell us which product is the best. W: Do they? I don't think so. Every manufacturer says that his product is the best, or at least tries to give the impres-sion. Only one can be the best, so the others are misleading, aren't they? M: Well, in a way, I suppose, but we don't have to believe them, do we? W: Are you saying that advertisements aren't effective? I don't think that intelligent businessmen will spend millions of dollars on advertising if nobody believes the advertisements, do you? M: Perhaps not, but after all, it's their money that they are spending. W: Is it? I think not. The cost of advertising is added to the price of the article. You and I and all the other people who buy the article pay for the advertising. M: Well, I suppose we get something for our money, some information. W: Yes, but don't forget it is often misleading information, and sometimes harmful. M: Harmful? W: What about the advertisements designed to persuade young people to smoke cigarettes? Wouldn't you say they are harmful? M: You've given me a lot to think about. I'm quite looking forward to the debate now. According to the woman, advertisements ______ .