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Unit 6 When was it invented?
Paul: Hey Roy, the subject _____my school project is “Small inventions that ______ the world." Can you help me think of an __________?
Roy: ____________________! Let me think .... hmm .. I know! The zipper!
Paul: The zipper? Is it really ______________________?
Roy: Think about ______________ it’s ______ in our daily lives.You can see zippers _______ dresses,trousers, shoes, bags .. almost everywhere!
Paul: Well, you do seem to __________________ .
Roy: Of course! I thought about it because I saw a website last week。 The pioneers of different inventions_________________there. For example, it ___________ that the zipper _______________ Whitcomb Judson in 1893。 But at that time, it wasn’t used widely.
Paul:Really? So when did it__________________ popular?
Roy:Around 1917.
An Accidental Invention
Did you know that tea, the most popular drink in the world (after water), _____ (invent) by accident? Many people believe that tea was first _____(drink) nea