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语言朋友(25)：35 am on December 17, he first successful airplane for 12 seconds and 120 feet along a beach in Kitty Hawk, North Carolina.With Orville flying first, the brothers took turns as pilot, and they flew three more times that day.On their fourth try, they managed to go 852 feet in 59 seconds － an amazing feat at the time.The two brothers had invented powered flight.By repairing bicycles, they had learned how gears and pulleys worked.They also learned to take careful notes about what they saw.Each time they made a new design and tested a machine, they took notes and made drawings.They would study these to figure out what they could do better the next time. Before the Wright brothers flew, they did many things to prepare for this extraordinary achievement.They read everything they could find about air, balloons, and kites.Then they made careful sketches of what they wanted to build.They began by making model kites to learn how air flowed over wings.They made them bigger and bigger until they had a glider － a kite that is big enough to hold a person, ng their first airplane.Each time they made a glider, they would test it, make careful observations, and then improve their design. When they made a glider that flew well, they added an engine.This step was harder than it sounds, because they had to find an engine that was both lightweight and powerful.The engines that they could buy were either too heavy or too weak, so they asked their friend Charlie Taylor to help them build one.The first engine that Charlie built broke almost immediately, but the second one worked well. | 
