【正确答案】
【答案解析】Invention of telephone.
[听力原文]
"I know it can be done, and I"m going to find the way." These words of determi-nation were spoken by Alexander Graham over a hundred years ago when he told scientists that he was trying to send human speech over an electric wire. Bell"s determination resulted in the invention of the telephone.
Born in Scotland in 1847, Alexander Bell became interested very early in the methods of human communication. While he was young, he taught speech at a school. His free time was spent in doing experiments on the characteristics of sound. In his experiments he made an interesting discovery. By starting and stopping the flow of electric current through a coil of copper wire, he found he could produce noises from the coil. It would not, however, carry the sound of the human voice.
To solve the problem, Bell knew he had to get help of someone who knew electricity well. Not long after, he found Thomas Watson, an electrician. Having got Watson"s help, Bell started to work at once. That was in 1875. As spring turned into summer, Bell and Watson worked night and day. They worked on, and summer was followed by autumn and winter. Then, on March 10, 1876—success.
That day Bell and Watson were at their posts, several rooms apart, ready to begin another experiment. While working, Bell got his leg injured, and he cried for help. "Mr. Watson, come here, I want you!" And Mr. Watson heard Bell crying over his receiver. That was the first sentence ever spoken over a telephone.
Having found the solution, Bell and Watson continued to work, trying to improve their telephones. Two years later, telephones were installed in many cities in the United States. The number of telephones in use kept going up very fast year after year, and in 1922 there were over 20 million telephones in the United States.
But on August 2 of that year, 1922, all of these telephones were silenced. At the age of seventy-five Alexander Graham Bell died. During his funeral all the telephones in North America were silenced in tribute to him.
Today, we all look up our heads at the telephone wires that carry our words from one place to another, we can almost hear the hum of communications that Bell compared to singing: "The singing never stops," he said, "for it is singing the story of life, and life never stops. Those copper wires up there are carrying all kinds of news from station to station around the world."