[外语类试卷]大学英语六级模拟试卷637及答案与解析.doc

1、大学英语六级模拟试卷 637及答案与解析 一、 Part I Writing (30 minutes) 1 1. 现代生活充满压力 2. 压力的种种迹象 3. 如何减轻压力 How to Reduce Stress and Tension 二、 Part II Reading Comprehension (Skimming and Scanning) (15 minutes) Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions att

2、ached to the passage. For questions 1-4, mark： Y (for YES) if the statement agrees with the information given in the passage; N (for NO) if the statement contradicts the information given in the passage; NG (for NOT GIVEN) if the information is not given in the passage. 1 Part Reading Comprehension

3、(Skimming and Scanning) Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions on Answer Sheet 1. For questions 1-7, choose the best answer from the four choices marked A), B), C) and D). For questions 8-10, complete the sentences with the informat

4、ion given in the passage. Satellite Today, you see compact satellite dishes perched on rooftops all over the United States. Drive through rural areas beyond the reach of the cable companies and youll find dishes on just about every house. The major satellite television companies are bringing in more

5、 customers every day with the lure of movies, sporting events and news from around the world. The Broadcast TV Problem Conceptually, satellite television is, a lot like broadcast television. Its a wireless system for delivering television programming directly to a viewers house. Both broadcast telev

6、ision and satellite stations transmit programming via a radio signal. Broadcast stations use a powerful antenna to transmit radio waves to the surrounding area. Viewers can pick up the signal with a much smaller antenna. The main limitation of broadcast television is range. The radio signals used to

7、 broadcast television shoot out from the broadcast antenna in a straight line. In order to receive these signals, you have to be in the direct “line of sight“ of the antenna. One problem is that the Earth is curved, so it eventually breaks the signals line of site. The other problem with broadcast t

8、elevision is that the signal is often distorted even in the viewing area. To get a perfectly clear signal like you find on cable, you have to be pretty close to the broadcast antenna without too many obstacles in the way. The Satellite TV Solution Satellite television solves the problems of range an

9、d distortion by transmitting broadcast signals from satellites orbiting the Earth. Since satellites are high in the sky, there are a lot more customers in the line of site. Satellite television systems transmit and receive radio signals using specialized antennas called satellite dishes. The televis

10、ion satellites are all in geosynchronous orbit, meaning that they stay in one place in the sky relative to the Earth. Each satellite is launched into space at about 7,000 mph (11,000kph), reaching approximately 22,200 miles (35,700km) above the Earth. At this speed and altitude, the satellite will r

11、evolve around the planet once every 24 hoursthe same period of time it takes the Earth to make one full rotation. In other words, the satellite keeps pace with our moving planet exactly. This way, you only have to direct the dish at the satellite once, and from then on it picks up the signal without

12、 adjustment, at least when everything works right. The Overall System Early satellite TV viewers were explorers of sorts. They used their expensive dishes to discover unique programming that wasnt necessarily intended for mass audiences. The dish and receiving equipment gave viewers the tools to pic

13、k up foreign stations, live feeding between different broadcast stations, NASA activities and a lot of other stuff transmitted using satellites. Some satellite owners still seek out this sort of programming on their own, but today, most satellite TV customers get their programming through a direct b

14、roadcast satellite (DBS) provider, such as Direct TV or the Dish Network. The provider selects programs and broadcasts them to subscribers as a set package. Basically, the providers goal is to bring dozens or even hundreds of channels to your television in a form that approximates the competition, c

15、able TV. Unlike earlier programming, the providers broadcast is completely digital, which means it has much better picture and sound quality. Early satellite television was broadcast in C-band radio radio in the 3.4-gigabertz (GHz) to 7-GHz frequency range. Digital broadcast satellite transmits prog

16、ramming in the Ku frequency range (12 GHz to 14 GHz ). The Programming Satellite TV providers get programming from two major sources: national turnaround channels (such as HBO, ESPN and CNN) and various local channels (NBC, CBS, ABC, PBS and Fox affiliates in a particular area). Most of the turnarou

17、nd channels also provide programming for cable television, and the local channels typically broadcast their programming over the airwaves. Turnaround channels usually have a distribution centre that beams their programming to a geostationary satellite. The broadcast centre uses large satellite dishe

18、s to pick up these analogs and digital signals from several sources. The broadcast centre converts all of this programming into a high-quality, uncompressed digital stream. At this point, the stream contains a vast quantity of dataabout 270 megabits per second (Mbps) for each channel. In order to tr

19、ansmit the signal from there, the broadcast centre has to compress it. Otherwise, it would be too big for the satellite to handle. Compression, Encryption and Transmission The two major providers in the United States use the MPEG-2 compressed video format the same format used to store movies on DVDs

20、. With MPEG-2 compression, the provider can reduce the 270-Mbps stream to about 5 or 10 Mbps (depending on the type of programming). This is the crucial step that has made DBS service a success. With digital compression, a typical satellite can transmit about 200 channels. Without digital compressio

21、n, it can transmit about 30 channels. At the broadcast centre, the high-quality digital stream of video goes through an MPEG-2 encoder, which converts the programming to MPEG-2 video of the correct size and format for the satellite receiver in your house. After the video is compressed, the provider

22、needs to encrypt it in order to keep people from accessing it for free. Encryption scrambles the digital data in such a way that it can only be decrypted (converted back into usable data) if the receiver has the correct decryption algorithm and security keys. Once the signal is compressed and encryp

23、ted, the broadcast centre beams it directly to one of its satellites. The satellite picks up the signal with an onboard dish, amplifies the signal and uses another dish to beam the signal back to the Earth, where viewers can pick it up. The Dish and the Receiver A satellite dish is just a special ki

24、nd of antenna designed to focus on a specific broadcast source. The standard dish consists of a parabolic (bowl-shaped) surface and a central feed horn. To transmit a signal, a controller sends it through the horn, and the dish focuses the signal into a relatively narrow beam. The end component in t

25、he entire satellite TV system is the receiver. The receiver has four essential jobs: It de-scrambles the encrypted signal. In order to unlock the signal, the receiver needs the proper decoder chip for that programming package. It takes the digital MPEG-2 signal and converts it into an analog format

26、that a standard television can recognize. In the United States, receivers convert the digital signal to the analog NTSC format. Some dish and receiver setups can also output an HDTV signal. It extracts the individual channels from the larger satellite signal. When you change the channel on the recei

27、ver, it sends just the signal for that channel to your TV. It keeps track of pay-per-view programs and periodically phones a computer at the providers headquarters to communicate billing information. While digital broadcast satellite service is still lacking some of the basic features of conventiona

28、l cable (the ability to easily split signals between different TVs and VCRs, for example), its high-quality picture, varied programming selection and extended service areas make it a good alternative for some. With the rise of digital cable, which also has improved picture quality and extended chann

29、el selection, the TV war is really heating up. 2 Broadcast stations use _to transmit radio waves to the surrounding area. （ A） a powerful antenna （ B） a much smaller antenna （ C） satellite dishes （ D） cable 3 The television satellites stay in geosynchronous orbit and_. （ A） transmit signal in the di

30、rect “line of sight“ （ B） compress the signal （ C） keep pace with the moon （ D） keep pace with the earth 4 In recent years, satellite television has started to be broadcast in the radio frequency range_. （ A） between 3.4 GHz and 7 GHz （ B） between 12 GHz and 14 GHz （ C） between 14 GHz and 21 GHz （ D

31、） between 21 GHz and 27GHz 5 Local television channels usually use _to transmit their programming. （ A） satellites （ B） cable （ C） airwaves （ D） wires 6 Satellite television providers can bring dozens or even hundreds of channels to TV viewers because_. （ A） satellite can send more programs （ B） the

32、 television signals sent to satellites are compressed （ C） the signals are encrypted （ D） the signals converted back into usable data 7 _receives satellite television signal and decodes it for the TV screen. （ A） The satellite dish （ B） The provider （ C） The receiver （ D） The viewer 8 Satellite TV h

33、as encountered fierce competition from digital cable, which also has （ A） improved picture quality （ B） extended channel selection （ C） distorted signal （ D） both A and B 9 Satellite television is similar to broadcast television in the way that it is _for sending television programming directly to a

34、 viewers home. 10 In the United States, the two major providers of direct broadcast satellite television are_. 11 The satellite television signal is transmitted in the digital video format of_. Section A Directions: In this section, you will hear 8 short conversations and 2 long conversations. At th

35、e end of each conversation, one or more questions will be asked about what was said. Both the conversation and the questions will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked A, B, C and D, and decide which is the best answer

36、. （ A） The woman thinks Joseph will remarry. （ B） Joseph will not remarry in fear that he might feel disappointed again. （ C） Joseph doesnt want to remarry because he hates being cheated. （ D） Joseph doesnt like the woman. （ A） The man and the woman are going to get married. （ B） The woman wants to

37、invite many people to the wedding ceremony. （ C） The woman wants the man to agree with her idea. （ D） The man doesnt want to invite many people to their wedding ceremony. （ A） The man didnt see eye to eye with Professor Clark. （ B） The man caught the most important point of the topic. （ C） The mans

38、presentation had a right purpose. （ D） The man was right to give the presentation. （ A） The woman shouldnt believe everything Dave tells her. （ B） The woman shouldnt let Dave get the best of her. （ C） Dave is not serious with the woman. （ D） Dave is always true to his words. （ A） Everyone in the tow

39、n misses Lots. （ B） Everyone in the town expects Lora to come hack. （ C） Everyone in the town respects Lora. （ D） Everyone in the town wants to see Lots. （ A） Hurry to the conference. （ B） Skip the conference. （ C） Take the subway. （ D） Take a bus. （ A） He is confident. （ B） He is worried. （ C） He i

40、s bored. （ D） He is angry. （ A） He used to be a workman himself. （ B） He likes to do repairs and make things himself. （ C） He is professional builder. （ D） He paid workmen to decorate the house. 20 What do we learn about the man from the conversation? （ A） He wants to sign a long-term contract. （ B）

41、 He is good at both language and literature. （ C） He prefers teaching to administrative work. （ D） He is undecided as to which job to go for. 21 What do we learn about the students at the Polytechnic? （ A） They hate exams. （ B） They all plan to study in Cambridge. （ C） They are all adults. （ D） They

42、 are going to work in companies. 22 What does the woman think of the job at the Language school? （ A） Difficult but rewarding. （ B） Varied and interesting. （ C） Time-consuming and tiring. （ D） Demanding and frustrating. （ A） The root of Jims health problems. （ B） The womans problems with her workaho

43、lic professor. （ C） Jims relationship with his professor. （ D） Problems that Jim and the woman have with their workloads. （ A） Whether to accept the Deans job offer or not. （ B） Whether to move or not. （ C） whether to have a rest or not. （ D） whether to ask for an extension or not. （ A） See more of

44、her. （ B） Spend more time in school. （ C） Earn more money. （ D） Get better gradel （ A） She would like to mark papers, too. （ B） She wants to ask for a light load to her professor. （ C） She wants the man to talk to the workaholic professor. （ D） She wants to quit school and work. Section B Directions

45、: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D. （ A） There is an office fur

46、niture show. （ B） There is a painting exhibition. （ C） There is a modern art contest. （ D） There is an off-season sale. （ A） Quite impressive. （ B） Rather meaningless. （ C） Absolutely childish. （ D） Extremely funny. （ A） His painting is a mess. （ B） His painting does not belong to art. （ C） He feels

47、 terrible while painting his picture. （ D） Georges mother has made the same comment. （ A） Matter has different laws. （ B） Matter has one common law. （ C） Matter shares the same laws. （ D） Matter shares no common law. （ A） The planet must be as big and heavy as the earth. （ B） Proper conditions are e

48、ssential to the existence of life. （ C） Double stars can provide steady light and heat. （ D） The distance between a planet and its sun should be right. （ A） The author is optimistic. （ B） The author is pessimistic. （ C） The author is aggressive. （ D） The author is ambitious. （ A） It has a personal s

49、tyle. （ B） It sounds very familiar to our ears. （ C） It is one whose style you cannot recognize. （ D） It does not belong to any composer. （ A） It combines different feelings together. （ B） It can express some very confusing feelings. （ C） It exaggerates some special feelings. （ D） It expresses feelings in an appropriate way. （ A） The newer the music is, the longer time it will last. （ B） It is easy for music to gain a permanent status. （ C） Good music always stands the test of time. （ D） Good musi