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Chicago, the birthplace of the skyscrapers, started to build upwards in 1871 after the great fire. These buildings consisted of ten to twelve storeys and differed in the way they were built from other buildings. Conventional buildings have walls which support the building’s weight, whereas skyscrapers have walls which are thin and light and attached to a metal frame.
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Conventional buildings have walls …
differed in the way they were built
which are thin and light
which are attached to a metal frame
which support the building’s weight