听力原文：W: Hello. What's all this then, Harry? M: What's all what? I'm making a cake. W: Yes. We can see what you're up to. Obviously you're making a cake. What else would you be doing with a cake tin and a rolling pin on the table and the place absolutely covered in flour? Yes, we can see what you're doing. But why are you doing it? M: Well, I just decided I'd try and make one for a change instead of buying one. Anyway this is going to be a rather special sort of cake. You can't buy them like this. And while you're here, Doris, do you mind beating up half a dozen eggs in that blue bowl over there? You'll find a fork and egg whisk, whichever you prefer, in the drawer on the left. W: OK. I don't mind. But what's so special about this cake? M: It's a surprise cake. W: A surprise cake? M: Yes. Doris, don't forget to add five spoons of sugar. W: No, dear. But tell us about this surprise cake. M: Well, it was an idea I had while I was lying in bed last night. W: Do you usually think of food in bed? M: I wasn't thinking of food. I decided to have a party for some old friends of mine, but I want to give them a surprise. W: What kind of surprise? M: Can you add a half of a pint of cream to that, Doris? That's right, drip it in slowly and then beat it up again until it becomes all sticky. That's the way. W: I have made a cake before, you know. Now, come on, what's the surprise? M: Well, it's quite simple, really. You see, I serve the cake with candles on it. Then I switch out the lights and I slip out of the room. But before this I tell them that they must count to twenty before trying to blow out the candles and they'll get a surprise. W: And then?(Explosion effect) (20)