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The elevator is a very useful (a) because it allows people to travel very quickly to the top of tall (b). The first elevators were very different from those of today. They had a simple (c) on which people stood and animals or people pulled on (d) to lift the platform. Later, in the twelfth century, some priests who lived on a mountaintop made an elevator for visitors. In the eighteenth century, Villayer invented a flying chair that used a (e) in a shaft. This was a popular invention, but a French princess was hurt in one when the rope broke. This continued to be a problem until the mid-nineteenth century when Elisha Otis came up with a way to prevent the elevator from (f) if the rope broke. When (g)was discovered, elevators could be operated without the use of animals or people, but they did not become completely safe until the use of (h).
platform
ropes
invent
electric
counterweight
fell
build
steam power
* You may need to change the form of some of the words.
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