阅读理解。 根据短文内容,完成下面的句子，每空一词。 There are few families in the United States that do not have either a radio or television set. Both of them have become a necessary part of our daily life, keeping us filled with the news of the day, teaching us in many fields of interest, and making us happy with singing, dancing and acting. Marconi, the Italian inventor, who gave us the radio, probably didn't know how much his great invention would have done for the world in the years to come. Radio had perhaps done as much as any other communication tool. Things of the world can be reported to people everywhere a few seconds after they happened. Travelers in out-of-the-way places, ships at sea and even astronauts traveling round the earth are able to keep in touch with each other by radio. Television is another important invention. It lets us see as well as hear the actor. Since its appearance, TV has done a great deal in the daily life of people everywhere. Many programs are now televised (播放) in color. Perhaps the most modem invention is 'Telstar', a 'star' moving round the earth. It makes it possible for the people all over the world to be closer than ever before. Now a family in Chicago can watch on TV a motor-car race in Italy, a table tennis competition in Beijing or a volleyball match in Japan when these events are actually happening! 1. We can know from the passage that a of families in America have radios or television sets. 2. Radio and TV have become a ______ part of our daily life because they have _____ nearly everything in our life. 3. When the writer introduces Marconi in the second paragraph, he means his ______ has much for the world. 4. Since television ,it has made a great-_______ to our daily life. 5. According to the passage'Telstar' is used to help _____ radio or TV information to the people _____ the world.