Many objects in the universe are invisible ，but they send radio waves．The radio telescope *thus appeared，and it is considered one of the greatest inventions in the twentieth century．Reber built the world's first radio telescope in 1937．Ryle and Hewish developed radio telescope systems for the location of weak radio sources，and they shared the Nobel Prize for Physics in 1974．
A radio telescope is usually made up of：
•One or more antennas to collect the radio waves．Most antennas are made in the shape of a dish to collect and reflect *the radio waves to the sub﹣reflector，in the same way as a curved mirror focuses visible light to one point．
•A receiver and amplifier to receive the radio waves from the sub﹣reflector，and make these weak radio waves strong enough to be recorded and turned into electronic signals *．To make an amplifier sensitive enough，it is usually cooled to very low temperatures（e．g．as low as ﹣270℃）．
•A recorder to keep a record of the electronic signals．Most radio telescopes today keep the signals to the computer's memory disk for astronomers to analyze later．
Radio wavelengths are much longer than those of visible light．and the radio waves from deep space are always weak．To catch these waves，radio telescopes usually have huge antennas．The sizes of most antennas in use today are around 50 to 300 metres in diameter． The antenna of FAST in Guizhou，China，the latest and largest radio telescope in the world，is 500 metres in diameter，as large as the size of 30 football fields．
To avoid interferences， and keep the telescopes sensitive，radio telescopes are built in places where there are no human radio waves or electronic signals．For example，FAST is 5 kilometres away from the closest village and 25 kilometres away from the nearest town．
Radio telescopes create pictures of the sky，not in visible light， but in radio waves．This is extremely useful，because there are objects that can't be seen，objects that we wouldn't even know were there without radio telescopes．
（1）Radio telescopes help collect from the universe．
A．light
B．objects
C．radio waves
D．visible signals
（2）Most antennas of radio telescopes are made in the shape of a dish to ．
A．make the antennas strong enough
B．increase the number of radio waves
C．turn radio waves into electronic signals
D．focus radio waves on the sub﹣reflector
（3）The underlined word "interferences" in the passage refers to ．
A．the noises made by villagers and animals
B．the sounds from the radios and televisions
C．the people who go to Guizhou to watch FAST work
D．the radio waves and electronic signals from humans
（4）What have we done with the help of radio telescopes？
A．We have received pictures of deep space．
B．We have discovered unknown lives in the universe．
C．We have found some unknown objects in the universe．
D．We have turned the radio waves from space into light．
| Read the play and answer the questions. Place: A child’s room with white walls, a white chair, and a white bed. On the bed, there are some clothes. Character: A doll, who looks old and dirty, is sitting on the bed and speaking. The doll: She should be here soon. We will play some games today. (Three hour pass. NO ONE knocks on the door.) The doll: Just a few more seconds. We might play “try-on-new-clothes” today. (Five hours go by. NO SOUND is heard.) The doll: Maybe the school bus is late. Soon she’ll be here, and we’ll sing and dance together. (One day has flown away. The doll is still sitting on the bed, waiting.) The doll: Maybe tomorrow… I’m sure she’ll come tomorrow, and then we’ll play. (There in the room, the doll repeats the same story every day… ) & play 剧本 character 角色
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| The Flying Hat Shannon Blackman “The most sidesplitting story I’ve ever read. I couldn’t stop laughing after I finished it. Be ready to laugh your heart out.” Willy King, Best Book winner “It’s a story that makes you smile in your dreams. Blackman’s excellent writing cheers you up.” The tide, London “One of the best-selling books of the year. More than two million copies have been sold.” The Sunday Reader, New York “This book has become the talk of the country. The story is making its way into movie theaters. I can’t wait to see it!” Marian Miller, author of Ms. Lilly & comment 评论
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| Alice: Hi, Jerry, I heard you have fun with Peggy in Merry Park yesterday. Jerry: Yes. We had a great time there. Why didn’t you come with us? We got there by bus in only ten minutes. Alice: I know, but the ticket is more expensive on the weekend. Also, I’ve been there many times since it opened five years ago. Did you try the Dandelion Seat there? It’s so popular that people have to wait for over an hour to get a ride. Jerry: You mean those flower-like umbrellas that fly high in the sky? Alice: Yes. I enjoyed riding on the Dandelion Seat and looking over the city. It was a great experience. Jerry: Eh… I liked taking the train to get around the park better. I don’t think it’s fun to ride in the air. I’d feel like I could fall down any time. Alice: Maybe you would like it more at night. It’s wonderful to see the beautiful lights below your feet. Jerry: Well… I’m afraid of high places. Alice: Oh, I see. That’s too bad.
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| (At the beach) Ben: Hi, Judy! I can’t believe you came to join us! Judy: Hello, Ben. I came because I like your idea: when you give, you’re rich. I’m happy that I can do something for the Earth. Ben: Right. That’s why we had this plan to get our clean beach back. Do you know if Paul’s coming? I remember he had the same idea and said he would try his best to come over. Judy: But he just called and said he wouldn’t come today because it’s too hot. Ben: I can’t believe it! He always says, “We can do this and that….” Judy: Don’t you know him? He only pays lip service to what should be done but seldom does anything. Ben: I see. Let’s forget about him. We’ll have Tony and Sophie to help us soon. Judy: That’s great. So where should we start now? Should we pick up those bottles first? Ben: Sure, let’s go.
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| My family and I have ridden bikes around the island several times. My friends often ask me questions about biking with their families. I’m sorry to learn that some of them don’t really enjoy biking or get hurt on the road because they don’t prepare well. Here I want to share some things that I think are important before you start off: 1. Get a bike of the right size for everyone in your family. 2. Check every part of your bike carefully. 3. Lear to fix some easy bike problems. 4. Check the traffic and weather news. 5. Pack maps, warm clothes, raincoats, snacks and enough water.
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