补全对话。 选出能填入空白处的最佳选项，有两个多余选项。 A. What can I clean with such a duster? B. What are they made of? C. What shall I do? D. Can I help you? E. How can I remove dirty particles from it? F. Are they new materials? G. Then what’s the difference between this duster and the traditional ones? A: Good morning. 1 B: Yes. I’d like to buy a duster (掸子) A: Look at this one. It’s the newest. B: Oh, it looks nice and it’s so light. The feathers (羽毛) feel soft, too. 2 A: The feathers are made of space-age fibers (非常现代化的纤维). B: Spare-age fibers? 3 A: The traditional ones just move dust particles (尘埃) around while this duster attracts (吸引) dust particles and holds on to them. B: Really? 4 A: You can safely clean chairs, tables, beds, cupboards, TVs, chandeliers (吊灯), etc. B: 5 A: Put it into water each time after you have finished cleaning and it will become clean. B: They are really magic. I’ll take one.