Skyscrapers are very tall buildings in a city.  Looking up at them might make you dizzy (眩晕的).  Skyscrapers are a .wonder, whether (不管) you are looking up or down.

    How can the buildings be so tall? Something that happened during the 1880s made it possible.  First, a man named William Jenney got the idea of using a steel frame to hold up the walls and floors (钢架支撑墙壁和地面) of a building Jenney s idea made it possible to build taller buildings so he is called the "Father of the American skyscraper" Second, the elevators （电梯）improved. That helped people go up and down the tall buildings more easily."

    Back in the 1880s, Jenney s first tall building was 10 stories (楼层) high. In 2004, Taipei 101, at 101 stories high, became the tallest building in the world. But soon the Burj Khalifa in Dubai overtook it in 2010. The 828-meter building has 163 stories.

     For example, Shanghai Tower in China, One World Trade Center in the USA, Abraj Ai-Bait Clock Tower in Saudi Arabia, etc. All of them are really wonderful, aren't they?

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