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Since people first launched rockets into space in the 1950s, we have been leaving behind all sorts of things. Some of them, like the camera, were lost by astronauts while they did work outside their spacecraft. But much of the space junk is made up of little pieces of things that were once bigger objects, until they struck each other and broke apart.
Some things we send into space fall back toward Earth and burn up in the atmosphere. But larger pieces sometimes survive the extreme heat and hit the ground or the ocean at great speeds. So there is always concern that something may fall from the sky and do some harm. But space junk falling on roofs is not the biggest worry. Scientists are concerned about the “Kessler” problem. Imagine what happens when an empty rocket strikes another while orbiting the earth. Two big things become many smaller things. They then hit other things. The pieces get smaller and smaller until they form a cloud of junk that blocks the path of future space vehicles. Marco Castronuovo, an Italian Space Agency researcher, says launching a satellite into space that would get very close to some of the larger pieces of space junk. The satellite would connect a small rocket to the useless object. When the rocket explodes, it pushes the junk into a lower and slower orbit, nearer the Earth. After a time, the junk burns up in the atmosphere. Mr.Castronuovo has proposed using a number of small satellites with robotic arms. One arm would catch the space junk, and another arm would connect the rocket. He imagines that each satellite could jump from one large piece of junk to another. He thinks this method could destroy about ten large objects each year. Scientists have been concerned about space junk for many years. Right now, the costs of the cleanup have been too great. Mr.Castronuovo says his system could be put in place for a much more reasonable amount of money. So what can be done to clean up the space around our planet? 1.We can learn from the text that much of the space junk ________. A. was left by the astronauts on purpose B. is mainly made up of broken spaceship C. is usually made of small pieces of things D. burns up before it reaches the atmosphere 2.Now scientists are most worried that space junk will ________. A. harm the future space vehicles B. do some harm to the atmosphere C. fall on people's house roofs D. destroy the habitat of wildlife 3.It implies in the last but one paragraph that ________. A. clearing up the space will actually cost little B. small rockets also do harm to the atmosphere C. only robots can clear up the space completely D. it is still difficult for us to clear up the space 4.What is the text mainly about? A. Space junk threatens earth's orbital environment. B. Scientists use different methods to clear up space junk. C. Spacecrafts will meet with a lot of space junk in the future. D. Marco comes up with many methods to deal with space junk.
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The best kept secret in San Diego is waiting to offer you a delightful getaway—without leaving town. Less than three years ago, the Parisi Hotel was just an office building above the shops on the corner of Prospect Street. Now, that valuable space is an intimate luxury hotel with several rooms overlooking the ocean. You'll be amazed when you enter from the corner and ascend the curving staircase to the secondfloor lobby. It will take you into a different world.
What will you find when you enter the large contemporary lobby is a hand some and peaceful space that was designed with a hint of Tuscany in its modern Mediterranean style. The lobby has a large fire place with comfortable sofas in warm neutral colors surrounding it. You'll feel relaxed just sitting there—with its skylight overhead letting in the morning sun. All the rooms are more like suites (套间), with large comfortable beds, beautiful baths and stylish customdesigned furnishings and art throughout. The Parisi Hotel is the perfect place for seniors because it's quiet and restful—with only 20 rooms. You won't find many hotels like this in the center of a tourist town. The shops are all around you. Likewise for some of the city's best restaurants, you will never have to take your car out of the garage during your stay. And, by the way, the underground parking lot at the Parisi Hotel is free for hotel guests. Once you stay at this little gem (珍品), you'll want to return again and again. I know we do. It's a perfect place for seniors. Rates for standard suites begin at $ 275. You can call the hotel for reservation at (858)4541513. The Parisi Hotel is located at 1111 Prospect St. right across from La Valencia. 1.What does the underlined word “ascend” in Para.2 mean? A. Find. B. Change. C. Use. D. Climb. 2.When you enter the lobby, you will find that ________. A. it is decorated with Mediterranean furniture B. the walls are painted in bright colors C. a large fireplace is burning all the time D. sunlight comes through the window in the roof 3.The Parisi Hotel is perfect for old people because ________. A. all the rooms are like suites with beautiful ocean view B. it can give them the sense of peace C. it is convenient for them to go shopping D. it has stylish customdesigned furnishings and art throughout 4.According to the passage，________. A. the price of the suites in the Parisi Hotel varies B. the Parisi Hotel has furniture specially designed for old people C. the Parisi Hotel is located in a secret place in San Diego D. you must make a reservation before entering the hotel
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A little girl lived in a simple and poor house on a hill. Usually she ______ play in the small garden. She could see over the garden fence and across the valley a wonderful house with shining golden windows high on another hill.______ she loved her parents and her family, she desired to live in such a house and ______all day about how wonderful and exciting ______must feel to live there. At the age when she gained some ______ skill and sensibility (识别力), she ______ her mother for a bike ride ______ the garden. Her mother finally allowed her to go，______ her keeping close to the house and not ______ too far. The day was beautiful. The little girl knew______ where she was heading! ______ the hill and across the valley, she rode to the ______ of the golden house. ______ she got off her bike and put it against the gate post, she focused on the path______to the house and then on the house itself.She was very disappointed when she ______ that all the windows were ______ and rather dirty. So ______and heartbroken, she didn't go any further. She ______， and all of a sudden she saw an amazing ______. There on the other side of the valley was a little house and its windows were golden. Looking at her little home, she______ that she had been living in her golden house filled with love and care. Everything she dreamed was right there in front of her house. 1.A. might B. should C. would D. must 2.A. Unless B. Although C. Since D. But 3.A. dreamed B. worried C. asked D. shouted 4.A. this B. that C. it D. which 5.A. different B. scientific C. musical D. basic 6.A. begged B. blamed C. invited D. paid 7.A. inside B. outside C. through D. along 8.A. insisting on B. relying on C. arguing about D. wondering about 9.A. traveling B. running C. riding D. walking 10.A. madly B. rapidly C. exactly D. possibly 11.A. Over B. Down C. Around D. Beside 12.A. windows B. steps C. center D. gate 13.A. Until B. As C. While D. Because 14.A. getting B. introducing C. leading D. moving 15.A. felt B. learned C. concluded D. found 16.A. transparent B. bright C. plain D. wide 17.A. anxious B. angry C. serious D. sad 18.A. turned around B. cheered up C. settled down D. dropped in 19.A. hill B. valley C. background D. sight 20.A. imagined B. decided C. realized D. guessed
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—He tried to explain it to me but I just couldn't understand.Do you? —________. A. Not likely B. Not certainly C. Not really D. Not cleverly
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（题文）I thought I could continue to work here, but________I shall have to look for another job. A. in fact B. as it is C. as usual D. as is the case
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Emergency line operators must always calm and make sure that they get all the information they need to send help . A. grow B. appear C. become D. stay
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（题文）All the money ________， the young man had no choice but to start hunting for a job. A. has been spent B. had been spent C. having spent D. having been spent
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You should wear a shirt with long sleeves ________ you get burnt in the sun. A. in case B. so that C. although D. because
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（题文）To my ________， he was not a little ________ at the news that he had won the first prize in the English speech contest, for he thought that he didn't perform so well. A. astonishment；astonishing B. astonished；astonishing C. astonishment；astonished D. astonish；astonishment
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（题文）—Have you been to the Great Wall? —Perhaps not in my memory; ________， it might have been during the early childhood. A. if any B. if so C. if ever D. if not
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