人教版九年级全册unit6 When was it invented? SectionA 1a-2d第1课时课件（该课件内含频文件）（该课件包含单词语句听力）
Paul: Hey Roy, the subject for my school project is “Smallinventions that changed the world.” Can you help methink of an invention?
Roy: My pleasure! Let me think… hmm… I know! The zipper!
Paul: The zipper? Is it really such a great invention?
Roy: Think about how often it’s used in our daily lives. You cansee zippers on dresses, trousers, shoes, bags… almost everywhere!
Paul: Well, you do seem to have a point…
Roy: Of course! I thought about it because I saw a website last week. The pioneers of different inventions were listedthere. For example, it mentioned that the zipper was invented by Whitcomb Judson in 1893. But at that time, it wasn’t used widely.
Paul: Really? So when did it become popular?
Roy: Around 1917.
