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        12月英語四級(jí)考前每日一練(34)

        字號(hào):

        Directions: In this section, there is a passage with ten blanks. You are required to select one word for each blank from a list of choices given in a word bank following the passage. Read the passage through carefully before making your choices. Each choice in the bank is identified by a letter. Please mark the corresponding letter for each item on Answer Sheet 2 with a single line through the centre. You may not use any of the words in the bank more than once.
            Questions 47 to 56 are based on the following passage.
            Health effects from indoor air pollutants may be experienced soon after exposure or, possibly, years later. Immediate effects may show up after a single exposure or repeated exposures. These include irritation (不適) of the eyes, nose, throat,headaches, dizziness, and fatigue. Such immediate effects are 47 short-term and treatable. Certain immediate effects are similar to those from colds or other viral (病毒性的) diseases, so it is often difficult to determine if the symptoms are a result of 48 to indoor air pollution. For this reason, it is important to pay attention to the time and place 49 occur.
            Other health effects may show up either years after exposure has occurred or only after long or 50 periods of exposure. These effects, which 51 some breathing diseases, heart disease, and cancer, can be severely disabling or fatal. It is important to try to improve the indoor air quality in your home even if symptoms are not 52 .
            While pollutants commonly found in indoor air are 53 for many harmful effects, there is considerable 54 about what concentrations or periods of exposure are necessary to produce specific health problems. People also react very differently to exposure to indoor air pollutants. Further re- search is 55 to better understand which health effects occur after exposure to the average pollutant concentrations found in homes and which occurs from the 56 concentrations that occur for short periods of time.
            A.uncertainty F.repeated K.symptoms
            B.lower G.conditions L.unconsciousness C.exposure HI higher M.rarely
            D.show I.usually N.needed
            E.noticeable J.include 0.responsible Section B
            Directions : There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D.. You should decide on the best choice and mark the corresponding letter on Answer Sheet 2 with a single line through the centre.
            Passage One
            Questions 57 to 61 are based on the following passage.
            For years there have been endless articles stating that scientists are on the verge of achieving artificial intelligence, that it is just around the comer. The truth is that it may be just around the comer, but they haven't yet found the right clock.
            Artificial intelligence aims to build machines that can think. One immediate problem is to de- fine thought, which is harder than you might think. The specialists in the field of artificial intelligence complain, with some justification, that anything that their machines do is dismissed as not being thought. For example, computers can now play very, very good chess. They can't beat the greatest players in the world, but they can beat just about anybody else. If a human being played chess at this level, he or she would certainly be considered smart. Why not a machine? The answer is that the machine doesn't do anything clever in playing chess. It uses its blinding speed to do a brute-force (殘忍的) search of all possible moves for several moves ahead, evaluates the out- comes and picks the best. Humans don't play chess that way. They see patterns, which computers don't.
            This wooden approach to thought characterizes machine intelligence. Computers have no judgment, no flexibility, no common sense. So-called expert systems, one of the hottest areas in artificial intelligence, aim to mimic the reasoning processes of human experts in a limited field, such as medical diagnosis or weather forecasting. There may be limited commercial applications for this sort of thing, but there is no way to make a machine think about anything under the sun, which a teenager can do. The hallmark (特征) of artificial intelligence to date is that if a problem is severely restricted, a machine can achieve limited success. But when the problem is expanded to a realistic one, computers fall flat on their display screens. For example, machines can understand a few words spoken individually by a speaker that they have been trained to hear. They cannot understand continuous speech using an unlimited vocabulary spoken by just any speaker.
            57. From the passage we know that the author
            A.thinks that scientists are about to achieve artificial intelligence B.doubts whether scientists can ever achieve artificial intelligence
            C.does not think that scientists have found real artificial intelligence
            D is sure that scientists have achieved artificial intelligence.
            58. We learn from the second paragraph that __
            A.the writer thinks that the specialists complains have some reasons
            B.a(chǎn)nything that the computer does can be regarded as thought
            C.it is not very difficult to define thought
            D.computers play chess in exactly the same way as humans
            59. The advantage of the computer in playing chess lies in its
            A.cleverness in. thinking out original moves
            B.a(chǎn)bility to pick up the best out of all possible moves very quickly
            C.flexibility in choosing several different moves
            D.a(chǎn)bility to see patterns
            60. The characteristic of machine intelligence is its
            A.correct judgment
            B.high flexibility
            C.a(chǎn)bility to think about anything
            D.rigid approach to thought
            61. Which of the following statements about computers is true according to the passage?
            A Computers can beat any chess player in the world.
            B.Computers can never be used to forecast weather.
            C.Computers can be trained to understand some words spoken by a speaker.
            D.Computers can be made to think as a teenager does.
            【結(jié)構(gòu)剖析】議論文。本文談?wù)摿私陙硪恢贝嬖跔?zhēng)議的話題——人工智能。真正意義上的人工智能是否會(huì)實(shí)現(xiàn)?作者對(duì)此表示懷疑,并認(rèn)為無論怎樣人工智能都不可能克服其固有的局限性而超越人腦。