Planes have changed the world in the last hundred years. But this great change began with two ordinary people.
Orville and Wilbur Wright were two brothers. .They were good at making bicycles, but planes were their real interest.
At that time, people knew how to build and fly gliders. But nobody could build a plane with an engine and fly it. The plane builders had two main problems: . And the planes always crashed when they tried to take off.
The Wright brothers read about these problems in newspaper, and they decided to look for answers. They made small model planes in the bicycle shop and they built a wind tunnel(风道) to test the models. They also built real gliders. .
On December17th, 1903, Orville and Wilbur pulled The Flyer onto a flat sandy beach. The plane weighted 275 kilograms. It had a petrol engine and two wooden propellers(螺旋桨). Two bicycle chains connected the propellers to the engine. .The brothers threw a coin into the air to see who should fly first. Orville won. He climbed onto the plane and started the engine.
.Wilbur ran along beside the plane. And then the plane took off! It flew for only 12 seconds, but someone took a photograph, and the plane flew into the history books.
A. There was a wind about 30 kilometers per hour on that cold day.
B. Finally, they built a plane with an enginr calledThe Flyer.
C. They could not make the wings strong enough.
D. They had a bicycle shop in Ohio, USA.
E.The Flyerbegan to move into the wind.
