请将试题“已知a，b，，且a＜b，求证：”增加生活背景，使之具有一定的应用价值，并简析其内涵。
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Passage2Shay asked，“Do you think they'll let me play？”Shay's father knew that most of the boys would not want someone like Shay on their team，but the father also understood that if his son， mentally and physically disabled, were allowed to play, it would give him a much-needed sense of belonging and some confidence.Shay's father approached one of the boys on the field and asked if Shay could play, not expecting much. The boy looked around and said, "We' re losing by six runs and the game is in the eighth inning. I guess he can be on our team and we' ll try to put him in to bat in the final inning.Shay struggled over to the team's bench and put on a team shirt with a broad smile and his father had a small tear in his eye and warmth in heart. The boys saw the father's joy at his son being accepted.In the bottom of the eighth inning, Shay's team scored a few runs but was still behind by three. In the top of the final inning, Shay put on a glove and played in the field. Even though no hits came his way, he was obviously joyful just to be in the game and on the field. In the bottom of the final inning, Shay's team scored again. Now, Shay was scheduled to be next at bat. Would they let Shay bat and give away their chance to win the game?Surprisingly, Shay was given the bat. Everyone knew that a hit was almost impossible. The first pitch came and Shay missed. The pitcher again took a few steps forward to throw the ball softly towards Shay. As the pitch came in, Shay swung at the ball and hit a slow ground ball right back to the pitcher.The pitcher could have easily thrown the ball to the first baseman and Shay would have been out and that would have been the end of the game. Instead, the pitcher threw the ball right over the head of the first baseman, beyond the reach of all teammates. The audience and the players from both teams started screaming,"Shay, run to first!"Never in his life had Shay ever run that far but made it to first base, wide-eyed and shocked.Everyone shouted, "Run to second!"Catching his breath, Shay awkwardly ran towards second. By the time Shay rounded towards second base, the smallest guy on their team, who had a chance to be the hero for his team for the first time, could have thrown the ball to the second baseman, but he understood the pitcher's intentions and he too intentionally threw the ball high and far over the third baseman's head.All were screaming, "Shay, Shay, Shay, all the way Shay."Shay reached third base when one opposing player ran to help him and shouted,"Shay, run to third."As Shay rounded third, all were on their feet, crying,"Shay, run home!"Shay ran to home, stepped on the home base and was cheered as the hero who won the game for his team.That day, the boys from both teams helped bring a piece of true love and humanity into this world. Shay didn't make it to another summer and died that winter, having never forgotten being the hero and making his father so happy and coming home and seeing his mother tearfully hug her little hero of the day!Not expecting much, Shay's father still asked the boy if Shay could play, mainly because the father_______.
A、noticed some of the boys on the field were heisting
B、guessed his presence would affect the boy's decision
C、learned some of the boys on the field knew Shay well
D、understood Shay did need a feeling of being accepted
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Passage2Can electricity cause cancer？In a society that literally runs on electric power，the very idea seems preposterous.But for more than a decade，a growing band of scientists and journalists has pointed to studies that seem to link exposure to electromagnetic fields with increased risk of leukemia and other malignancies.The implications are unsettling，to say the least，since everyone comes into contact with such fields，which are generated by everything electrical，from power lines and antennas to personal computers and micro-wave ovens. Because evidence on the subject is inconclusive and often contradictory，it has been hard to decide whether concern about the health effects of electricity is legitimate-or the worst kind of paranoia.Now the alarmists have gained some qualified support from the U.S.Environmental Protection Agency. In the executive summary of a new scientific review，released in draft form late last week，the EPA has put forward what amounts to the most serious government warning to date.The agency tentatively concludes that scientific evidence"suggests a casual link”between extremely low-frequency electromagnetic fields-those having very long wave-lengths-and leukemia，lymphoma and brain cancer，While the report falls short of classifying ELF fields as probable carcinogens，it does identify the common 60-hertz magnetic field as"a possible，but not proven，cause of cancer in humans.”The report is no reason to panic-or even to lost sleep.If there is a cancer risk，it is a small one.The evidence is still so controversial that the draft stirred a great deal of debate within the Administration，and the EPA released it over strong objections from the Pentagon and the White House.But now no one can deny that the issue must be taken seriously and that much more research is needed.At the heart of the debate is a simple and well-understood physical phenomenon: When an electric current passes through a wire, it generates an electromagnetic field that exerts forces on surrounding objects. For many years, scientists dismissed any suggestion that such forces might be harmful, primarily because they are so extraordinarily weak. The ELF magnetic field generated by a video terminal measures only a few milligauss, or about one-hundredth the strength of the earth' sown magnetic field, the electric fields surrounding a power line can be as high as 10 kilovolts permeter, but the corresponding field induced in human cells will be only about 1 millivolt per meter. This is far less than the electric fields that the cells themselves generate.How could such minuscule forces pose a health danger? The consensus used to be that they could not, and for decades, scientists concentrated on more powerful kinds of radiation, like X-rays, that pack sufficient wallop to knock electrons out of the molecules that make up the human body. Such"ionizing"radiations have been clearly linked to increased cancer risks and there are regulations to control emissions.But epidemiological studies, which find statistical associations between sets of data, do not prove cause and effect. Though there is a body of laboratory work showing that exposure to ELF fields can have biological effects on animal tissues,a mechanism by which those effects could lead to cancerous growths has never been found.The Pentagon is far from persuaded. In a blistering 33-page critique of the EPA report, Air Force scientists charge its authors with having "biased the entire document"toward proving a link. "Our reviewers are convinced that there is no suggestion that(electromagnetic fields) present in the environment induce or promote cancer,"the Air Force concludes."It is astonishing that the EPA would lend its imprimatur on this report."Then Pentagon's concern is understandable. There is hardly a unit of the modern military that does not depend on the heavy use of some kind of electronic equipment, from huge ground-based radar towers to the defense systems built into every warship and plane.The main idea of this passage is______.
A、studies on the cause of cancer
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教师教学柳永的《雨霖铃·寒蝉凄切》时，向学生强调合理地使用不同意象对渲染气氛、奠定情感基调具有重要的作用。下列诗歌意象与《雨霖铃·寒蝉凄切》中“寒蝉”“长亭”所渲染的气氛、表达的情感基本一致的是()。
A、五柳
B、双鲤
C、南浦
D、流水
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玄奘根据自己西天取经的见闻写成（ ）。
A、《大唐西域记》
B、《西域历险记》
C、《唐三藏西天取经》
D、《西游记》
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阅读一高中教师教授必修5《陈情表》的课堂实录回忆（节选），回答下面问题。（画线语句的序号与选项的序号是对应的） [A]课前预习指导：查找并印发了《陈情表》一课相关的背景资料和历代名家的品评文字。 [B]让学生在第一遍阅读时找出难点，通过查找工具书的方式将难点字词的义项了解清楚。并通过对照课文，确定词语在文章中的意思。之后，分组归纳出公认的难解词语，师生讨论解决。帮助学生顺利通过文言文阅读的语言关。 [C]导语：讲述以“忠情”感人的诸葛亮《出师表》的主要内容，继而讲述”不下泪者必不友”的韩愈的《祭十二郎文》。之后直接点明本次课要讲以孝情动人的文章——《陈情表》。 [D]结束语：《陈情表》的动人之处就在于它陈孝情真意切。孝是中华民族的传统美德，十七八岁的年纪始终关注的永远是友情，深深憧憬的往往是爱情，最易忽略的却常常是亲情、孝情。 希望李密对祖母的乌鸟深情能让我们有所感悟，有所行动，为亲人奉上自己哪怕微薄但却真诚的回报。 对画线句子的分析错误的一项是（ ）。
A、让学生在真正接触课文之前产生好奇心，激起学生的阅读兴趣
B、体现了教师对学生的引导，锻炼了学生自己动脑、动手使用工具书等自主学习能力
C、导语恰当且富含知识性，能带领学生温习已有知识，自然进入新知识的学习
D、结束语的设计体现了“情感、态度和价值观”的目标，能达到对学生德育的目的