2014高频试卷完整版答案
2014年成人高考高起点英语考试真题及参考答案
一、语音知识：共5小题;每题1.5分，共7.5分。
在下列每组单词中，有一个单词的划线部分与其他单词的划线部分的读音不同。
找出这个词。
1. 请选择出划线部分读音不同的选项( )。
A. batheB. birthC. thoughtD. Thank【答案】A2. 请选择出划线部分读音不同的选项( )。
A. aliveB. monitorC. mindD. Bicycle【答案】B3. 请选择出划线部分读音不同的选项( )。
A. potatoB. policeC. populationD. Polite【答案】C4. 请选择出划线部分读音不同的选项( )。
A. gatherB. giftC. generalD. goat【答案】C5. 请选择出划线部分读音不同的选项( )。
A. featherB. headC. breadD. Beeach【答案】D二、词汇与语法知识：共15小题;每题1.5分，共22.5分。
从每小题的四个选择项中，选出最佳的一项。
6. The doctor told Mr. White that he couldn' t get better if he didn't_________drinking.A. give upB. give awayC. give inD. give out【答案】A【应试指导】本题考查动词短语辨析。
句意：医生告诉怀特先生，如果他不戒烟身体就不能康复。
give up意为“放弃，戒除”;9ive away意为“泄露，失去”;give in意为“屈服，投降”;9ive out意为“发布，停止运行”。
根据句意可知，应选A。
7. It was a pity that he missed the meeting__________in London last month.A. to be heldB. heldC. having heldD. to hold【答案】B【应试指导】本题考查非谓语动词。
江苏省_2014年_高考英语真题(附答案+听力mp3)_历年历届试题(解析)
2014年江苏高考英语试题第一部分听力（共两节,满分20 分）做题时,先将答案标在试卷上. 录音内容结束后,你将有两分钟的时间将试卷上的答案转涂到答题卡上。
第一节(共5 小题;每小题1 分,满分5 分）听下面5 段对话。
每段对话后有一个小题，从题中所给的A、B、C 三个选项中选出最佳选项，并标在试卷的相应位置。
听完每段对话后,你都有10 秒钟的时间来回答有关小题和阅读下一小题。
每段对话仅读一遍。
例：How much is the shirt？A。
£ 19。
15。
B。
£ 9。
18. C。
£ 9。
15。
答案是C。
1. What does the woman want to do？A。
Find a place. B。
Buy a map. C. Get an address。
2. What will the man do for the woman？A. Repair her car.B. Give her a ride.C. Pick up her aunt。
3. Who might Mr. Peterson be?A. A new professor。
B。
A department head。
C。
A company director。
4. What does the man think of the book？A. Quite difficult. B。
Very interesting。
C。
Too simple。
5。
What are the speakers talking about?A. Weather。
B。
Clothes。
C。
News。
第二节（共15 小题；每小题 1 分,满分15 分）听下面5 段对话或独白。
每段对话或独白后有几个小题,从题中所给的A、B、C 三个选项中选出最佳选项，并标在试卷的相应位置. 听每段对话或独白前,你将有时间阅读各个小题,每小题 5 秒钟；听完后，各小题给出 5 秒钟的作答时间. 每段对话或独白读两遍。
高频电子线路试卷与答案11
标准答案(一)一、填空题〔每空1分，共30分〕1、无线电通信中，信号是以电磁波形式发射出去的。
它的调制方式有调幅、调频、调相。
2、针对不同的调制方式有三种解调方式，分别是检波、鉴频、和鉴相。
3、在单调谐放大器中，矩形系数越接近于1、其选择性越好；在单调谐的多级放大器中，级数越多，通频带越窄、〔宽或窄〕，其矩形系数越〔大或小〕小。
4、调幅波的表达式为：uAM〔t〕= 20〔1 +0.2COS100πt〕COS107πt〔V〕；调幅波的振幅最大值为24V，调幅度Ma为20℅，带宽fBW为100Hz，载波fc为5*106Hz。
5、在无线电技术中，一个信号的表示方法有三种，分别是数学表达式、波形、频谱。
6、调频电路有直接调频、间接调频两种方式。
7、检波有同步、和非同步检波两种形式。
8、反响式正弦波振荡器按照选频网络的不同，可分为LC、RC、石英晶振等三种。
9、变频器可由混频器、和带通滤波器两部分组成。
10、列出三个常见的频谱搬移电路调幅、检波、变频。
11、用模拟乘法器非线性器件实现调幅最为理想。
二、选择题〔每题2分、共20分〕将一个正确选项前的字母填在括号内1、以下哪种信号携带有调制信号的信息〔C 〕A、载波信号B、本振信号C、已调波信号2、小信号谐振放大器的主要技术指标不包含〔B 〕A、谐振电压增益B、失真系数C、通频带D、选择性3、丙类谐振功放其谐振回路调谐于〔 A 〕分量A、基波B、二次谐波C、其它高次谐波D、直流分量4、并联型石英晶振中，石英谐振器相当于〔C 〕元件A、电容B、电阻C、电感D、短道路5、反响式正弦波振荡器的起振条件为〔 B 〕A、|AF|=1，φA+φF= 2nπB、|AF| >1，φA+φF = 2nπC、|AF|>1，φA+φF ≠2nπD、|AF| =1，φA+φF ≠2nπ6、要实现集电极调制特性应使功放工作在〔B 〕状态A、欠压状态B、过压状态C、临界状态D、任意状态7、自动增益控制可简称为〔 B 〕A、MGCB、AGCC、AFCD、PLL8、利用非线性器件相乘作用来实现频率变换其有用项为〔 B 〕A、一次方项B、二次方项C、高次方项D、全部项9、如右图所示的电路是〔D 〕A、普通调幅电路B、双边带调幅电路C、混频器D、同步检波器10、在大信号包络检波器中，由于检波电容放电时间过长而引起的失真是〔B〕A、频率失真B、惰性失真C、负峰切割失真D、截止失真三、判断题，对的打“√〞,错的打“×〞〔每空1分，共10分〕1、谐振放大器是采用谐振回路作负载的放大器。
高频试卷(答案)
4.变容二极管调频器实现线性调频旳条件是变容二极管旳结电容变化指数γ为( C）A．１/3 Ｂ．1/２ C.2 D.41３．运用石英晶体旳电抗频率特性构成旳振荡器是（B) A．f＝ｆs时,石英晶体呈感性，可构成串联型晶体振荡器B．f=fs时，石英晶体呈阻性，可构成串联型晶体振荡器C．f s<f<fp时,石英晶体呈阻性,可构成串联型晶体振荡器D．f s<f＜fp时,石英晶体呈感性,可构成串联型晶体振荡器4.小信号谐振放大器旳重要特点是以调谐回路作为放大器旳交流负载,具有放大和选频功能。
5. 谐振功率放大器旳调制特性是指保持Ｕbm及Ｒp不变旳状况变化,或随U CC变化旳特性。
下,放大器旳性能随UＢB三、简答题（每题5分，共10分）1．当谐振功率放大器旳输入鼓励信号为余弦波时,为什么集电极电流为余弦脉冲波形?但放大器为什么又能输出不失真旳余弦波电压?答:由于谐振功率放大器工作在丙类状态(导通时间不不小于半个周期）,因此集电极电流为周期性余弦脉冲波形;但其负载为调谐回路谐振在基波频率,可选出ic旳基波,故在负载两端得到旳电压仍与信号同频旳完整正弦波。
五、下图所示二极管峰值包络检波电路中，ｕ（t)=0.8（1+0．８cosΩt)cosωcＡMｔ（ｖ）, 其中f c＝4.7MHz，F=（１00~5０00）Ｈz，ＲL=５KΩ,为了不产生惰性失真和底部切割失真，求检波电容ＣL和电阻Ｒ｀L旳值（10分)解：为了不产生惰性失真, 解得40.6pF ≤C L ≤０.0047ｕF 为了不产生底部切割失真， 解得R ｀Ｌ≥20 k Ω1．在调谐放大器旳LC 回路两端并上一种电阻R,可以 （ C ） A.提高回路旳Q 值 Ｂ.提高谐振频率 Ｃ．加宽通频带 Ｄ．减小通频带 12.ＡGＣ电路旳作用是( C ）C ．使输出信号幅度保持恒定或仅在很小旳范畴内变化二、填空题（每题2分，共10分)1．石英晶体振荡器是运用石英晶体旳 压电和反压电效应 工作旳,其频率稳定度很高,一般可分为 串联型晶体振荡器 和 并联型晶体振荡器 两种。
2014专四真题及答案详解
TEST FOR ENGLISH MAJORS (2014)-GRADE FOUR-TIME LIMIT: 135 MINPART I DICTATION [15 MIN] Listen to the following passage. Altogether the passage will be read to you four times. During the first reading, which will be done at normal speed, listen and try to understand the meaning. For the second and third readings, the passage will be read sentence by sentence, or phrase by phrase, with intervals of 15 seconds. The last reading will be done at normal speed again and during this time you should check your work. Y ou will then be given 2 minutes to check through your work once more. Please write the whole passage on ANSWER SHEET ONE.PART II LISTENING COMPREHENSION [20 MIN] In Sections A, B and C you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. Mark the best answer to each question on Answer Sheet Two.SECTION A CONVERSATIONSIn this section you will hear several conversations. Listen to the conversations carefully and then answer the questions that follow.Questions 1 to 3 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions. Now, listen to the conversation.1.What are they mainly talking about in the conversation?A.Transport.B. Customers.C. Relocation.D. Restaurants.2.Which of the following is mentioned by Tim as a good reason for moving?A.More office space.B. Convenient parking.C. Fewer office workers.D. A near-by train station.3.Why is Jane worried about winter in the new location?A.It is much colder there.B. There are few activities.C. There are no good restaurants.D. There is no cinema or theatre.Questions 4 to 7 are based on the following conversation. At the end of the conversation, you will be given 20 seconds to answer the questions. Now, listen to the conversation.4.Miss Parkinson became interested in her own business _______.A.before she worked for the media companyB. when she was on holiday five years agoC. after she went to therapists and classesD. after her friend recommended it to her5.Why did she ask her teachers to teach her at home?A.She was busier than before.B. It was more convenient.C. She liked to exercise at home.D. She was given a promotion.6.Which of the following is NOT true according to the conversation?A.She recommended people to take classes.B. She was willing to pay more for classes at home.C. She left her job immediately after her promotion.D. She regarded the business as a pastime at first.7.Why did she finally leave her job?A.She got bored with her job.B. She saw an opportunity.C. She needed the money.D. She was forced to leave.Questions 8 to 10 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions. Now listen to the conversation.8.Which of the following is NOT mentioned about the single-lens reflex?A.Different lenses can be used.B. Focusing is easier.C. You can see what you are taking.D. It is cheaper and lighter.9.According to the shop assistant, the main difference between the two types of cameras lies in _______.A.lensB. priceC. weightD. size10.It can be inferred from the conversation that the customer is more likely to buy _______ in the end.A. a single-lens cameraB. nothingC. a rangefinder cameraD. several lenses instead SECTION B PASSAGESIn this section, you will hear several passages. Listen to the passages carefully and then answer the questions that follow. Questions 11 to 13 are based on the following passage. At the end of the passage, you will be given 15 seconds to answer the questions. Now, listen to the passage.11.Which of the following details about the front of the house is CORRECT?A.The front is pink.B. The curtain is drawn.C. No window can be seen.D. There are two doors.12.What is to the immediate left side of the house?A. A washing line.B. Another house.C. A flat area.D. A chimney.13.Where is the small town in the picture?A.Between two hills.B. Further to the left of the house.C. At the back of the house.D. At the side of ahill.Questions 14 to 17 are based on the following passage. At the end of the passage, you will be given 20 seconds to answer the questions. Now, listen to the passage.14.When did Ben first become interested in Mongolia?A.When he grew up.B. When he learned Mongolian.C. When he returned home.D. When he was nine years old.15.Where did he spend most of his teenage years?A.In Mongolia.B. In the Arab world.C. In his hometown.D. In some other regions.16.We learn from the passage that Ben _______ while doing his master’s degree.A.became interested in classical MongolianB. learned classical and modern MongolianC. gave up modern MongolianD. mastered modern Mongolian17.Which of the following details is NOT true according to the passage?A.Ben wants to visit Mongolia when the weather is warm.B. Ben considers the travel expense reasonable.C. The trip today is expensive considering inflation.D. Ben was unable to travel to Mongolia in 1971. Questions 18 to 20 are based on the following passage. At the end of the passage, you will be given 15 seconds to answer the questions. Now, listen to the passage.18.Which is the height of towers at Sky Greens vertical farm?A.9 meters.B. 20 meters.C. 100 meters.D. 40 meters.19.Which of the following is NOT true according to the passage?A.The farm sells its vegetables to a local supermarket.B. The farm uses less water and energy to growvegetables. C. The farm causes less pollution in its production. D. The farm sells at the same price as imported produce20.According to the passage, one particular advantage of the Sky Green is _______.A.local climateB. local supportC. plan for expansionD. closeness to the citySECTION C NEWS BROADCASTIn this section, you will hear several news items. Listen to them carefully and then answer the questions that follow. Questions 21 and 22 are based on the following news. At the end of the news item, you will be given 10 seconds to answer the questions. Now. listen to the news.21.According to the passage, Turkish police were unsure about _______.A.when the woman was killedB. the main cause of the deathC. the woman’sidentity D. why she failed to return home22.How many people had been detained by Turkish police?A.9.B. 19.C.22.D. 33.Questions 23 and 24 are based on the following news. At the end of the news item, you will be given 10 seconds to answer the questions. Now, listen to the news.23.What is the situation now in Kidal according to the news?A.Islamist militants are still in control of the town.B. French forces have entered the town.C. French are going to land at the airport.D. Islamist militants are attacking the airport.24.Why did the French launch the military operation?A.To control Kidal airport.B. To protect the town.C. To protect the capital Bamako.D. To fight against Islamist militants.Questions 25 and 26 are based on the following news. At the end of the news item, you will be given 10 seconds to answer the questions. Now, listen to the news.25.Which of the following is TRUE about the immigration reform?A.It was proposed by a group of senators.B. Mr Obama had carried out the reform.C. Illegal immigrants would soon be given citizenship.D. The reform failed to improve the current system.26.According to Obama’s 2011 blueprint, how long would it take for illegal immigrants to gain citizenship?A.Eight years.B. Five years.C. Thirteen years.D. Eleven years. Questions 27 and 28 are based on the following news. At the end of the news item, you will be given 10 seconds to answer the questions. Now, listen to the news.27.What is Lorraine Melvill’s business?A.Running a plastic surgery clinic.B. Arranging for surgery and safaris.C. Providing consultancy to local people.D. Organizing trips to UK and American.28.Which of the following statements is NOT true according to the news item?A.Local African clients helped keep her business going.B. Her clients were unable to pay her the money.C. Her business was affected by the global financial crisis.D. She still had as many European clients as before. Questions 29 is based on the following news. At the end of the news item, you will be given 5 seconds to answer the question. Now, listen to the news.29.What is the main idea of the news item?A.Foreign investment in unstable regions.B. BP’s presence in North Africa.C. Security concerns in risky countries.D. Protection for foreign oil workers.Questions 30 is based on the following news. At the end of the news item, you will be given 5 seconds to answer the question. Now, listen to the news.30.What is the main message of the news item?A.London attracts shoppers from all over the world.B. Most people in Nigeria live in poverty.C. Wealthier Nigerians become a big spender.D. People from the Middle East are the most wealthy.PART III CLOZE [15 MIN] Decide which of the choices given below would best complete the passage if inserted in the corresponding blanks. Mark the best choice for each blank on ANSWER SHEET TWO.The Victorians had become addicted to speed and they wanted to go ever faster. Time was money and efficiency became (31)____ important. Although divisions of labour had been (32)____ by Adam Smith and illustrated by a pin factory in The Wealth of Nations in 1776, (33)____ could now become fully realised. This specialization of labour was in (34)____ contrast to the rural means of production, in (35)____ the family was the means of production, consumption and socialization. (36)____ greater speed came a greater need for industries and businesses to make more and make it quicker. Steam made this (37)____ and changed working life forever (38)____ were the days when work was (39)____ by natural forces: steam engines were servant (40)____ neither season nor sunshine. Factories had foremen and life became correspondingly more (41)____. The clocking-on machine was (42)____ in 1885 and time and motion studies to increase efficiency would be introduced only (43)____ twenty years later. (44)____ it was not all bad news. Agricultural incomes depended on variable harvests and weather. Factories provided (45)____ and predictable income, but long hours.Working life was becoming increasingly regulated, and the working (46)____ was reorganised to promote ever-greater efficiency. The old (47)____ St. Monday - when no work was done - was (48)____, work stopped around midday on Saturday and did not resume (49)____ Monday morning. A new division between “work” and “leisure” emerged, and this new block of weekend leisure time coincided with the development of spectator sports like cricket and football, and the (50)____ of music hall entertainment for the new working classes.31. A. increasingly B. surprisingly C. slowly D. obviously32. A. contributed B. informed C. spread D. conceived33. A. he B. it C. these D. those34. A. clear B. marked C. apparent D. firm35. A. that B. what C. where D. which 36. A. UponB. OverC. WithD. For37. A. possible B. practical C. worthwhile D. useful38. A. Passed B. Lost C. Gone D. Missed39. A. defined B. controlled C. limited D. dictated40. A. over B. on C. by D. to41. A. standard B. controlled C. difficult D. dreadful42. A. designed B. created C. invented D. bought43. A. some B. certain C. these D. those44. A. For B. But C. Consequently D. Accordingly45. A. safe B. good C. continuous D. secure46. A. week B. period C. pattern D. practice47. A. culture B. behaviour C. custom D. habit48. A. repair B. compensate C. mend D. moderate49. A. before B. until C. on D. after50. A. raise B. increase C. trend D. presentPART IV GRAMMAR & VOCABULARY [15 MIN]There are thirty sentences in this section. Beneath each sentence there are four words, phrases or statements marked A, B, C and D. Choose one word, phrase or statement that best completes the sentence. Mark your answers on ANSWER SHEET TWO.51.It is essential that he ________ all the facts first.A.is examiningB. will examineC. examinesD. examine52.Which of the following sentences expresses a future action?A.Lucy is continually finding fault with her sister.B. We are meeting the visitors after the performance.C. The coach is now crossing the Garden Bridge.D. I’m hoping that you’ll give us some advice.53.Which of the following italicized parts is used as an object complement?A.The front door remained locked.B. The boy looked disappointed.C. Nancy appeared worried.D. He seemed to have no money left.54.Which of the following sentences is INCORRECT?A.Physics is an important school subject.B. The Niagara Falls is in North America.C. The United States borders Canada.D. Mumps is a kind of infectious disease.55.Which of the following sentences indicates POSSIBILITY?A.The moon cannot always be at the full.B. You cannot smoke inside the building.C. He cannot come today.D. She cannot play the piano.56.The boys in the family are old enough for ________.A.schoolsB. schoolC. the schoolD. the schools57.Which of the following italicized parts indicates a predicate-object relationship?A.He was reading Mary’s letter in the room.B. You can buy men’s shoes in this shop.C. Mrs. Black’s passport was lost.D. The enemy’s defeat brought the war to an end.58.Please pardon ________ you.A.my disturbingB. disturbing meC. to disturbD. that I disturb59.Which of the following tag questions is INCORRECT?A.Carry this parcel for me, will you?B. Nobody wants to go there, does he?C. Few people know him, don’t they?D. Everything is ready, isn’t it?60.Which of the following reflexive pronouns（反身代词）is used as an object?A.I spoke to the president himself.B. Frank is not quite himself today.C. Linda herself will play the violin.D. You must pull yourself together.61.The research team can handle ________ needs to be handled.A.wheneverB. whicheverC. whereverD. whatever62.Which of the following italicized parts modifies an adverb?A.I rather like my teacher.B. That was a very funny film.C. Do it right now.D. We walked about6 miles.63.When the sentence “They had made a mess of the house” is turned into passive voice, which of the following isCORRECT?A. A mess had been made in the house.B. A mess had been made by them.C. The house had been made a mess of.D. The house had been made a mess.64.Fool ________ Michael is, he could not have done such a thing.A.asB. whoC. thatD. like65.When the sentence “Shall I drive you to the airport first?” is turned into indirect speech, which of the following ismost appropriate?A.He agreed to drive me to the airport first.B. He offered to drive me to the airport first.C. He advised me to go to the airport first.D. He suggested that I drive to the airport first.66.The interviewers were impressed by the high calibre of the applicants for the job. The underlined part means________.A.criterionB. qualityC. qualificationD. level67.Her career has ________ a number of activities — composing, playing and acting.A.heldB. producedC. embracedD. combined68.The operation could ________ her life by two or three years.A.prolongB. increaseC. expandD. continue69.All her cousins and their children have fair hair. The underlined part means ________.A.fineB. darkC. thickD. light70.John always feels sluggish first thing in the morning. The underlined part means ________.A.sickB. inactiveC. dizzyD. drowsy71.The family of the victim had to endure a long wait before the case cane to trial. The underlined part means ________.A.tolerateB. keepC. faceD. hold72.The chief of surgery became committee chairman by virtue of ________.A.seniorityB. serviceC. ageD. rank73.He turned his back on them when they most needed him. The underlined part means ________.A.criticizedB. ignoredC. betrayedD. deceived74.Our school did not ________ for Christmas until mid-December.A.break outB. break downC. break upD. break in75.The flags in the stadium ________ in the wind.A.flappedB. movedC. shookD. stirred76.His mother retired early on account of poor health. The underlined part means ________.A.despiteB. withC. according toD. because of77.The whole country was in ________ over the result of the elections.A.suspensionB. suspenseC. suspendingD. suspender78.There is no conceivable reason why there should be any difficulty during the project. The underlined part can bereplaced by all the following EXCEPT ________.A.thinkableB. imaginableC. possibleD. observable79.The employers prepared, with all due ________ for a conference with the Trade Unions.A.cautionB. concernC. certaintyD. consideration80.Our experiment was conducted under optimal conditions. The underlined part means ________.A.perfectB. properC. possibleD. proposedPART V READING COMPREHENSION [25 MIN]In this section there are four passages followed by questions or unfinished statements, each with four suggested answers marked A, B, C and D. Choose the one that you think is the best answer. Mark your answers on ANSWER SHEET TWO.TEXT AAfter breakfast the boys wandered out into the play-ground. Here the day-boys were gradually assembling. They were sons of the local clergy, of the officers at the Depot, and of such manufacturers or men of business as the old town possessed. Presently a bell rang, and they all trooped into school. This consisted of a large, long room at opposite ends of which two under masters conducted the second and third forms, and of a smaller one, leading out of it, used by Mr. Watson, who taught the first form. To attach the preparatory to the senior school these three classes were known officially, on speech days and in reports, as upper, middle, and lower second. Philip was put in the last. The master, a red-faced man with a pleasant voice, was called Rice; he had a jolly manner with boys, and the time passed quickly. Philip was surprised when it was quarter to eleven and they were let out for ten minutes' rest.The whole school rushed noisily into the play-ground. The new boys were told to go into the middle, while the others stationed themselves along opposite walls. They began to play Pig in the Middle. The old boys ran from wall to wall while the new boys tried to catch them: when one was seized and the mystic words said - one, two, three, and a pig for me - he became a prisoner and, turning sides, helped to catch those who were still free. Philip saw a boy running past and tried to catch him, but his limp gave him no chance; and the runners, taking their opportunity, made straight for the ground he covered. Then one of them had the brilliant idea of imitating Philip’s clumsy run. Other boys saw it and began to lau gh; then they all copied the first; and they ran round Philip, limping grotesquely, screaming with shrill laughter. They lost their heads with the delight of their new amusement, and choked with helpless merriment. One of them tripped Philip up and he fell, heavily as he always fell, and cut his knee. They laughed all the louder when he got up. A boy pushed him from behind, and he would have fallen again if another had not caught him. The game was forgotten in the entertainment of Philip’s deformity. Philip was completely scared. He could not make out why they were laughing at him. His heart beat so that he could hardly breathe, and he was more frightened than he had ever been in his life. He stood still stupidly while the boys ran round him, mimicking and laughing; they shouted to him to try and catch them; but he did not move. He did not want them to see him run any more. He was using all his strength to prevent himself from crying.81. From the beginning of the passage we learn that ________.A. some pupils came from the local areaB. the school only accepted day-boysD. Philip’s class was part of the senior schoolC. the school had only three classes82. What was Philip’s reaction to his class?A. He thought class was too short.B. He found his class surprising.C. He seemed to have enjoyed it.D. He wanted to change class.83. In the game Philip lost his ground because ________.A. the game wasn’t fit for new boys like himB. the playground wasn’t big enough for the gameC. he did not know the rules of the gameD. he could not run as quickly as other boys84. What did the boys do after Philip lost his ground?A. They continued with the game.B. They stopped to make fun of him.C. They changed to another game.D. They stopped and went inside.85. How did Philip feel in the end?A. He was ashamed of himself.B. He was very nervous.C. He was really horrified.D. He felt himself stupid.TEXT BFor parents who send their kids off to college saying, “These will be the best years of your life,” it would be very appropri ate to add, “If you can handle the stress of college life.”Freshmen are showing up already stressed out, according to the latest research study that reported students’ emotional health levels at their lowest since the survey started in 1985. While in school, more students are working part-time and near-full-time jobs. At graduation, only 29 percent of seniors have jobs lined up.Pressure to excel often creates stress, and many students are not learning how to effectively handle this stress. Let me show five facts that I believe every college student should know about stress.First, stress can make smart people do stupid things. Stress causes what brain researchers call “cortical inhibition.” In simple terms, stress inhibits a part of the brain responsible for decision-making and reaction time and can adversely affect other mental abilities as well.Second, the human body doesn’t discriminate between a big stressful event and a little one. Any stressful experience will create about 1,400 biochemical events in your body. If any amount of stress is left unchecked, many things can occur within the body, including premature aging, impaired cognitive function and energy drain.Third, stress can become your new pattern. When you regularly experience negative feelings and high amounts of stress, your brain recognizes this as your normal state. This then becomes the new norm, or baseline for your emotional state.Fourth, stress can be controlled. Countless studies demonstrate that people can restructure their emotional state using emotion-refocusing techniques. These techniques help you recognize how you are feeling and shift to a more positive emotional, mental and physical state.One technique involves slowing your thoughts and focusing on your heartbeat, breathing slowly and deeply, and focusing on the positive feeling that you receive.Finally, stress can be lessened by loving what you study. Barbara Frederickson, a leading international authority on the importance of positive emotions, says humans are genetically programmed to seek positive emotions such as love and joy. It's suggested to choose a major or career path you love and enjoy. Otherwise, you could end up fighting against your own biology.86.The author cites the latest research study in order to show that ________.A.students are studying harder in collegeB. most students have part-time job nowC. stresscontinues to the time of graduation D. students only feel stressed while in school87.According to the passage, stress might cause all the following negative effects EXCEPT ________.A.socialB. mentalC. emotionalD. physical88.In the author’s opinion, stress can be controlled by ________.A.doing what you preferB. identifying your present emotional state firstC. finding a more positive feeling firstD. focusing on your emotional state89.According to the conte xt, what does “your own biology” mean in the last paragraph?A.Your current major.B. Your future job.C. Your future research.D. Your preference.90.Which of the following is the best as the title of the passage?A.Causes of Stress.B. Type of Stress. CollegeC. Life and Stress.D. Stress and ControlMethods.TEXT CFor anyone who doubts that the texting revolution is upon us, consider this: The average 13- to 17-year-old sends and receives 3,339 texts a month—more than 100 per day, according to the Nielsen Co., the media research firm. Adults are catching up. People from ages 45 to 54 sent and received 323 texts a month in the second quarter of 2010, up 75% from a year ago, Nielsen says.Behind the texting explosion is a fundamental shift in how we view our mobile devices. That they are phones is increasingly beside the point.Part of what's driving the texting surge among adults is the popularity of social media. Sites like Twitter, with postings of no more than 140 characters, are creating and reinforcing the habit of communicating in micro-bursts.Economics has much to do with texting’s popularity. Text messages cost carriers less than traditional mobile voice transmissions, and so they cost users less. Sprint Nextel has reconceived its Virgin Mobile brand to cater to heavy texters in a difficult economy. For $25 per month, users get unlimited texting, email, social networking and 300 talk minutes; for another $15, they get an additional 900 talk minutes. The name of the brand's new wireless plan: “Beyond Talk.”Texting’s rise over conversation is changing the way we interact, social scientists and researchers say. We are now inclined to text to relay difficult information. We stare at our phone when we want to avoid eye contact. Rather than make plans in advance, we engage in what research have named “micro-coo rdination”—”I’ll txt u in 10mins when I know wh/ restrnt.”Texting saves us time, but it steals from quiet reflection. “When people have a mobile device and have even a little extra ti me, they will communicate with someone in their life,” says Lee Rainie, director of the Pew Internet and American Life Project. And the phone conversation will never be completely obsolete. Deal makers and other professionals still spend much of the day on the phone. Researchers say people are more likely to use text-based communications at the preliminary stages of projects. The phone comes into play when there are multiple options to consider or important decisions to be made.91.At the beginning of the passage, the author uses figures for the purpose of ________.A.introductionB. comparisonC. explanationD. transition92.According to the context, which of the following is closest in meaning to “beside the point”?A.Unimportant.B. Unacknowledged.C. Underestimated.D. Undeniable.93.Which o f the following is NOT mentioned as a cause for texting’s popularity?A.Promotion of cheaper wireless packages.B. Increase in the number of adult texters.C. Redesign of mobile devices.D. Rise of social media.94.According to the passage, texting can help people to ________.A.face difficult situationsB. make appointments in advanceC. communicatewish strangers D. avoid awkward situations95.What is the passage mainly about?A.Texting’s popularity and effect.B. Role of texting in business.C. Preference to texting over thinking.D. Innovation of mobile devices.TEXT DThe healthy adolescent boy or girl likes to do the real things in life, to do the things that matter. He would rather be a pl umber’s mate and do a real job that requires doing than learn about hydrostatics sitting at a desk, without understanding what practical use they are going to be. A girl would rather look after the baby than learn about child care. Logically we should learn about things before doing them and that is presumably why the pundits enforce this in our educational system. But it is not the natural way-nor, I venture to think, the best way. The adolescent wants to do things first for only then does he appreciate the problems involved and want to learn more about them.They do these things better in primitive life, for there at puberty the boy joins his father in making canoes, patching huts, going out fishing or hunting. He is serving his apprenticeship in the actual accomplishments of life. It is not surprising that anthropologists(人类学家) find that the adolescents of primitive communities do not suffer from the same neurotic(神经质的) “difficulties” as those of civilized life. This is not, as some assume, because they are permitted more sexual freedom, but because they are given more natural outlets for their native interests and powers and are allowed to grow up freely into a full life of responsibility in the community.In the 19th century this was recognized in the apprenticeship system, which allowed the boy to go out with the master carpenter, or ploughman, to engage in the actual work of carpentry or roof-mending, and so to learn his trade. In some agricultural colleges at the present time young men have to do a year’s work on a farm before their theoretical training at college. The great advantage。
高频电子线路试卷及答案5
~ 学年第学期专业年级高频电子线路课程期末考试题A卷班级姓名学号得分一、选择题（每小题2分、共30分）将一个正确选项前的字母填在括号内1．改进型电容三点式振荡器的主要优点是（）A．容易起振B．振幅稳定C．频率稳定度较高D．减小谐波分量2．如图所示电路，以下说法正确的是（）A．该电路可以产生正弦波振荡B．该电路不能产生正弦波振荡，原因在于振幅平衡条件不能满足；C．该电路不能产生正弦波振荡，原因在于相位平衡条件不能满足；D．该电路不能产生正弦波振荡，原因在于振幅平衡、相位平衡条件均不能满足；3．功率放大电路与电压放大电路的区别是（）A．前者比后者电源电压高B．前者比后者电压放大倍数大C．前者比后者效率高D．前者比后者失真小4．如图所示为示波器测量正弦波波形参数的画面，若“TIME/DIV”的指示值是5μs，则所测正弦波的频率为（）A．100kHz B．50kHz C．25kHz D．20kHz5．小信号调谐放大器主要用于无线通信系统的（）A．发送设备B．接收设备C．发送设备、接收设备6．高频功率放大器主要工作在（）A．甲类B．乙类 C．甲乙类 D．丙类7．若载波u C(t)=U C cosωC t,调制信号uΩ(t)= UΩcosΩt，则双边带调幅波的表达式为（）A．u DSB(t)=U C cos（ωC t＋m a sinΩt）B．u DSB(t)=U C cos（ωC t＋m a cosΩt）C．u DSB(t)=U C（1＋m a cosΩt）cosωC t D．u DSB(t)=kUΩU C cosωC tcosΩt8．单频调制时，调频波的最大频偏Δf m正比于（）A．UΩB．uΩ(t)C．Ω9．鉴相的描述是（）A．调幅信号的解调B．调频信号的解调C．调相信号的解调10．下图所示框图能实现何种功能？（）其中u s(t)= U s cosωc tcosΩt， u r(t)= U r cosωc tA．振幅调制B．检波C．混频D．鉴频11．振荡器的相位平衡条件和振幅起振条件为（）A．φT（ω）＝2nл，T（jω）＝1B．φT（ω）＝0，T（jω）＝1C．φT（ω）＝2nл，T（jω）>112．调幅的描述（）A．用载波信号去控制调制信号的振幅，使调制信号的振幅按载波信号的规律发生变化。
高频电子线路试卷与答案
4、并联型石英晶振中，石英谐振器相当于（C ）元件A、电容B、电阻C、电感D、短路线5、反馈式正弦波振荡器的起振条件为（ B ）A、|AF|=1，φA+φF= 2nπB、|AF| >1，φA+φF = 2nπC、|AF|>1，φA+φF ≠2nπD、|AF| =1，φA+φF ≠2nπ6、要实现集电极调制特性应使功放工作在（B ）状态A、欠压状态B、过压状态C、临界状态D、任意状态10、在大信号包络检波器中，由于检波电容放电时间过长而引起的失真是（B）A、频率失真B、惰性失真C、负峰切割失真D、截止失真1、下列不属于小信号谐振放大器的技术指标是（C ）A、电压增益B、通频带C、非线性失真系数D、选择性2、某调幅广播电台的音频调制信号频率100Hz～8KHz ，则已调波的带宽为（ A ）A、16KHzB、200KHzC、4KHzD、8KHz3、对于同步检波器，同步电压与载波信号的关系是（C ）A、同频不同相B、同相不同频C、同频同相D、不同频不同相4、串联型石英晶振中，石英谐振器相当于（ D ）元件A、电容B、电阻C、电感D、短路线6、下列电路不属于频谱搬移电路的是（B ）A、调幅电路B、调频电路C、检波电路D、变频电路9、在大信号峰值包络检波器中，由于检波电容放电时间过长而引起的失真是（B ）A、频率失真B、惰性失真C、负峰切割失真D、截止失真10、要求本振信号功率大，相互影响小，放大倍数大，宜采用（ A ）混频电路A、基极输入，发射极注入B、基极输入，基极注入C、发射极输入，基极注入D、发射极输入，发射极注入1、谐振放大器处在谐振时其增益最大。
（√）2、小信号谐振放大器抑制比越大，其选择性越好。
（√）3、高频功放的动态线是一条直线。
（×）4、石英晶振可分为串联型和并联型。
（√）5、LC正弦波振荡器的振荡频率由反馈网络决定。
（×）6、利用非线性器件的相乘作用实现频谱搬移。
高频电子线路试卷及答案
⾼频电⼦线路试卷及答案⼀、单项选择题（本⼤题共10⼩题，每⼩题2分，共20分）1．欲提⾼⾼频功率放⼤器的效率，应使放⼤器的⼯作状态为（D）A．甲类B．⼄类C．甲⼄类D．丙类2．混频器⼲扰哨声的产⽣是由于（D）A．混频器前端电路的选择性不好B．外来⼲扰信号与本振的组合⼲扰C．外来⼲扰信号与有⽤信号的组合⼲扰D．混频器的⾮理想相乘特性产⽣的有⽤信号与本振的⾃⾝组合⼲扰3．调频波的特点是（A）A．载波频率随调制信号的⼤⼩⽽变化B．载波频率随调制信号的频率⽽变化C．载波幅度随调制信号的频率⽽变化D．载波的附加相移随调制信号频率⽽变化4．调制信号为uΩ(t)=UΩcosΩt,载波信号为uc(t)=Uccosωct，则表达式uo(t)=Ucos(ωct+msinΩt)是（C）A．普通调幅波B．抑制载波双边带调幅波C．调频波D．调相波2．欲提⾼功率放⼤器的效率，应使放⼤器的⼯作状态为（D）A．甲类B．⼄类C．甲⼄类D．丙类3．为提⾼振荡频率的稳定度，⾼频正弦波振荡器⼀般选⽤（B ）A．LC正弦波振荡器B．晶体振荡器C．RC正弦波振荡器5．若载波u C(t)=U C cosωC t,调制信号uΩ(t)= UΩcosΩt，则调相波的表达式为（B）A．u PM(t)=U C cos（ωC t＋m f sinΩt）B．u PM(t)=U C cos（ωC t＋m p cosΩt）C．u PM(t)=U C（1＋m p cosΩt）cosωC t D．u PM(t)=kUΩU C cosωC tcosΩt．某调频波，其调制信号频率F＝1kHz，载波频率为10.7MHz，最⼤频偏Δf m＝10kHz，若调制信号的振幅不变，频率加倍，则此时调频波的频带宽度为（B）A．12kHz B．24kHz C．20kHz D．40kHz8．MC1596集成模拟乘法器不可以⽤作（D）A．混频B．振幅调制C．调幅波的解调D．频率调制9．某单频调制的普通调幅波的最⼤振幅为10v，最⼩振幅为6v，则调幅系数m a为（C）A．0.6 B．0.4 C．0.25 D．0.110．以下⼏种混频器电路中，输出信号频谱最纯净的是（C）A．⼆极管混频器B．三极管混频器C．模拟乘法器混频器11．某丙类谐振功率放⼤器⼯作在临界状态，若保持其它参数不变，将集电极直流电源电压增⼤，则放⼤器的⼯作状态将变为（D）A．过压B．弱过压C．临界D．⽋压12．鉴频的描述是（B）A．调幅信号的解调B．调频信号的解调C．调相信号的解调13．利⽤⽯英晶体的电抗频率特性构成的振荡器是（B）A．f＝fs时，⽯英晶体呈感性，可构成串联型晶体振荡器B．f＝fs时，⽯英晶体呈阻性，可构成串联型晶体振荡器C．fsD．fs14．下图所⽰框图能实现何种功能？（C）其中u s(t)= U s cosωs tcosΩt，u L(t)= U L cosωL tA ．振幅调制B ．调幅波的解调C ．混频D ．鉴频15．⼆极管峰值包络检波器，原电路正常⼯作。
2014年高考高频考点测试卷英语附答案
2014年高频考点测试卷英语学校姓名准考证号本试卷共10页，150分。
考试时长150分钟。
考生务必将答案答在答题卡上,在试卷上作答无效。
考试结束后，将本试卷和答题卡一并交回。
第I卷（共两部分，共115分）第一部分：听力（满分30分）第一节（共5小题；每小题1.5分，满分7.5分）听下面5段对话。
每段对话后有一个小题，从题中所给的A、B、C三个选项中选出最佳选项，并标在试卷的相应位置。
听完每段对话后，你都有10秒钟的时间来回答有关小题和阅读下一小题。
每段对话仅读一遍。
1．What time does the liberty open?A．At 7:30 B．At 8:00 C．At 8:302．How did Mary go to school today?A．By bike. B．On foot. C．By bus.3．Who regards gardening as play?A．The man. B．The woman. C．The man‘s wife.4．What does the woman use to learn Chinese?A．Radio. B．Television. C．Computer.5．Where are the two speakers?A．In a car shop. B．In a garage. C．In a parking lot.第二节（共10小题；每题1.5分，满分15分）听下面5段对话或独白。
每段对话或独白后有几个小题，从题中所给的A，B，C三个选项中选出最佳选项，并标在试卷的相应位置。
听每段对话或独白前，你将有时间阅读各个小题，每小题5秒钟；听完后，每小题将给出5秒钟的作答时间。
每段对话或独白读两遍。
听第6段材料，回答第6至7题。
6．What is the man doing?A．Offering help.B．Giving advice.C．Making appointments.7．What is the relationship between the two speakers?A．Doctor and patient. B．Husband and wife. C．Classmates.听第7段材料，回答第8至9题。
高频电子线路 试卷 答案
高频电子线路（电子）试卷（期中）一、填空题（共35分）1．LC串联谐振回路中，当工作频率小于谐振频率时，回路呈容性，LC并联谐振回路中，当工作频率小于谐振频率时，回路呈感性（2分）2. LC串联谐振回路中，当工作频率大于谐振频率时，回路呈感性，LC并联谐振回路中，当工作频率大于谐振频率时，回路呈容性。
（2分）3.衡量高频小信号放大器选择性的指标有矩形系数和抑制比。
（2分）4. 要观察调谐放大器的谐振曲线，需要的仪器是扫频仪。
（1分）5. 小信号调谐放大器的主要技术指标有增益、通频带、选择性、工作稳定性和噪声参数。
（2分）6. 单调谐放大器经过级联后电压增益增大、通频带变窄、选择性变好。
（3分）7．丙类高频功率放大器空载时工作于临界状态，当加上10kΩ负载时，其电流I c0和输出功率变化情况为Ic0略有增大（基本不变）， Po减小。
（2分）8. 发射机的中间级高频功率放大器，应工作于过压状态。
因为过压状态输出电压平稳且弱过压时，效率最高。
（2分）9. 高频功率放大器的三种工作状态，分别为过压、临界、欠压。
欲使功率放大器高效率地输出最大功率，应使放大器工作在临界状态；为了兼顾效率和功率，一般高频功率放大器的通角θ选为_700。
（4分）10. 发射机的末级高频功率放大器，应工作于临界状态，因为临界状态输出功率最大。
（2分）11. 丙类高频功率放大器原工作于临界状态，当其负载断开时，其电流Ic0、Ic1和功率变化情况为Ic0减小，Icm1减小， Po减小。
（3分）12．三端式振荡电路是LC正弦波振荡器的主要形式，可分为电容三端式和电感三端式两种基本类型。
（2分）13. 皮尔斯晶体振荡器中，石英晶体等效为电感元件。
（1分）14. 电感三点式振荡器的发射极至集电极之间的阻抗Z ce 性质应为__感___性，发射极至基极之间的阻抗Z be 性质应为__感___性，基极至集电极之间的阻抗Z cb 性质应为___容_性。
2014高考英语听力系列系列(4)及参考答案
2014高考英语听力系列系列（4）及参考答案第一部分：听力理解(共两节。
满分30分）第一节（共小题：每小题1．分，满分7．分)听下面段对话。
每段对话后有一个小题，从题中所给的A、B、C三个选项中选出最佳选项，并标在试卷的相应位置。
听完每段对话后，你都有10秒钟的时间来回答有关小题和阅读下一小题。
每段对话仅读一遍。
例：Hw h i the hirt?A ￡191B ￡91C ￡918答案是B。
1 What’ the tw peaker’ ajr？A MathB SpanihC Englih2 What de the ail ean？A He den't trt the wanB He wld like t try the new way nwC He wld take the ld way t the train tatin3 Where will the wan g nw?A ShanghaiB BeijingC Shenzhen4 Where de the nveratin prbably take plae？A In a retarantB In a htelC In a hpWh i Jdy?A Sa' wifeB Sa’ bine partnerC Sa' b第二节（共1小题，每小题1分，满分22分）听下面段对话或独白，每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项。
每段对话或独白听两遍.听第6段材料，回答6—7题。
6 What d we knw abt the wan？A She i ding badly n the nvelB She i gd at aking p trieC She han’t written any nvel befre7 Hw h ha the wan written the nvel nw？A Tw pageB Tw hapterC Jt a little听第7段材料,回答8—9题。
历史学基础(论述题)高频考点模拟试卷73(题后含答案及解析)
历史学基础（论述题）高频考点模拟试卷73(题后含答案及解析) 题型有：1.1．论述中国秦到清末的选官制度。
(兰州大学2014年历史学综合真题)正确答案：中国古代的官吏选拔制度主要经历了世袭制、察举制、九品中正制、科举制四个阶段。
(一)秦在商鞅变法时制定二十级爵。
制定二十级爵的作法，意味着废除旧世卿世禄制，今后根据人们的军功大小授予爵位，官吏从有军功爵的人中选用。
各级爵位均规定有占田宅、奴婢的数量标准和衣服等次。
又制定了“奖励军功，严惩私斗”的办法。
奖励军功的作法是：将卒在战争中斩敌首一个，授爵一级，可为五十石之官；斩敌首二个，授爵二级，可为百石之官。
宗室贵族无军功的，不得授爵位。
(二)察举制。
汉初，官吏主要有两个来源：一是按军功爵位的高低，选任各级官吏，故景帝以前，有“吏多军功”之说。
二是选自郎官，即郎中令属下的中郎、侍郎、郎中、议郎等。
郎官的职责是守卫宫殿和做皇帝随从，经过一段时间，中央或地方官有缺额，即可由郎官中选用。
到武帝时，军功地主已经没落，而郎官多出自“任子”或“赀选”，难以选拔到真正的人才。
因此，新儒学的代表董仲舒提出正式建立察举制度的主张。
他建议由列侯、二千石郡守，每年从地主阶级中推举茂才、孝廉各一人。
武帝采纳董仲舒的建议，于元光元年(前134年)冬，初令郡国每年举孝廉各一人。
从此之后郡国每年推举孝廉的察举制度正式确立。
除孝廉一科为察举取士的主要科目外，武帝还不定期设立茂才、贤良方正、文学等科察举取士，以广泛地吸收地主阶级中的优秀人才。
这些被察举到中央的人员，一般都在郎署供职，由郎官再逐渐升迁。
(三)九品中正制。
曹丕为争取世家大族的支持，接受了颍川士族陈群的建议，开始推行九品中正制度。
(1)内容。
九品中正制度，又称九品官人法。
其办法是：委任“贤有识鉴”的中央官吏兼任本州、郡、县的大小中正官，负责察访本州、郡、县散处在符地的士人，作出“品”“状”，供吏部选官参考。
所谓“品”，是综合士人德才、门第评定的等级，共分九品，大致二至三品为高品(一品为虚设，无人能达到)，四至五品为中品，六至九品为下品。
高考语文高频试卷及答案
一、现代文阅读（30分）阅读下面的文字，完成下面小题。
1. 下列关于《红楼梦》中贾宝玉形象的说法，不正确的一项是（）A. 贾宝玉具有叛逆精神，他反对封建礼教，追求个性解放。
B. 贾宝玉对女性充满同情，他尊重女性的独立人格。
C. 贾宝玉是典型的贵族公子形象，他生活奢侈，不问世事。
D. 贾宝玉对诗词歌赋有极高的天赋，他的诗词作品具有很高的艺术价值。
2. 下列关于《平凡的世界》中孙少平形象的说法，不正确的一项是（）A. 孙少平是一个具有强烈责任感的青年，他勇于面对生活的挑战。
B. 孙少平在追求爱情的道路上经历了许多波折，但他始终坚定自己的信念。
C. 孙少平具有浪漫主义情怀，他向往自由，追求理想。
D. 孙少平在事业上有很高的成就，他成为了一名优秀的工程师。
3. 下列关于《骆驼祥子》中祥子形象的说法，不正确的一项是（）A. 祥子是一个勤劳、朴实、善良的底层劳动者。
B. 祥子对生活充满希望，他渴望通过自己的努力改变命运。
C. 祥子最终被社会淘汰，他走向了堕落。
D. 祥子的悲剧命运是封建社会和旧制度造成的。
二、古诗文阅读（35分）阅读下面的诗文，完成下面小题。
【甲】青青园中葵，朝露待日晞。
阳春布德泽，万物生光辉。
常恐秋节至，焜黄华叶衰。
百川东到海，何时复西归？少壮不努力，老大徒伤悲。
【乙】白日依山尽，黄河入海流。
欲穷千里目，更上一层楼。
【丙】春眠不觉晓，处处闻啼鸟。
夜来风雨声，花落知多少。
1. 下列关于《青青园中葵》中诗句的理解，不正确的一项是（）A. “青青园中葵，朝露待日晞”表现了葵花对阳光的渴望。
B. “常恐秋节至，焜黄华叶衰”反映了诗人对时光流逝的忧虑。
C. “百川东到海，何时复西归？”表达了诗人对人生无常的感慨。
D. “少壮不努力，老大徒伤悲”告诫我们要珍惜时光，努力奋斗。
2. 下列关于《白日依山尽》中诗句的理解，不正确的一项是（）A. “白日依山尽，黄河入海流”描绘了壮丽的自然景色。
B. “欲穷千里目，更上一层楼”表达了诗人对远方的向往。
2014年英语高考试卷
2014年英语高考试卷提供2014年英语高考试卷答案：Section I: Listening Comprehension1. A2. C3. B4. A5. C6. B7. C8. A9. A 10. B11. C 12. A 13. B 14. C 15. A16. B 17. A 18. B 19. A 20. CSection Ⅱ: Grammar and Vocabulary21. D 22. C 23. A 24. B 25. A26. C 27. A 28. D 29. B 30. D31. C 32. A 33. B 34. D 35. C36. D 37. B 38. A 39. C 40. DSection III: Reading Comprehension41. D 42. A 43. B 44. C 45. D46. B 47. A 48. C 49. B 50. A51. C 52. D 53. A 54. B 55. C56. D 57. B 58. C 59. A 60. DSection IV: WritingPart A:61. Possible version:Dear Mr. Smith,I am writing to express my sincere apology for being late to the meeting yesterday. Due to unexpected traffic congestion, I arrived 15 minutes after the scheduled time. I understand the importance of punctuality in a professional setting and I assure you that this will not happen again in the future.I would like to make it up to you by offering to arrange another meeting at your convenience. Please let me know a time that works for you, and I will ensure that I am there on time.Once again, I apologize for any inconvenience my lateness may have caused. Thank you for your understanding.Sincerely,[Your Name]62. Possible version:Directions:For this part, you are allowed 30 minutes to write a composition on the topic My Ideal Job. You should write at least 120 words following the outline given below in Chinese.1. 描述你理想的工作是什么；2. 为什么它是理想工作；3. 为了实现这个工作目标，你要做的努力。
历史学基础(论述题)高频考点模拟试卷14(题后含答案及解析)
历史学基础（论述题）高频考点模拟试卷14(题后含答案及解析) 题型有：1.1．论述八旗制度的组织形式及其演变正确答案：八旗军队是清朝的主要军事力量。
1．八旗制度的组织形式：八旗制度是“以旗统人，即以旗统兵”的兵民一体、军政合一的社会组织形式。
八旗兵丁平时生产，战时出征。
八个固山额真即八旗旗主，都是由努尔哈赤的子、侄担任；他们既是军事统帅，又是各旗的政治首领。
努尔哈赤是八旗的家长和最高统帅。
八旗制度的实行，不仅提高了军事战斗力，也促进了满族社会的发展。
2．八旗制度的演变：八旗制度最初是由努尔哈赤在统一女真各部的过程中创立的。
以300人为一单位，称“牛录”，设牛录额真统辖；五牛录为一甲喇，设甲喇额真统辖；五甲喇为一固山，设一固山额真统辖。
共设八旗，分别是黄、白、红、蓝、镶黄、镶白、镶红、镶蓝，每旗7500人，八旗共6万人。
后来又设立了蒙古八旗和汉军八旗。
皇太极为了加强君权，将正黄、镶黄、正蓝三旗收归自己管辖，开创了清帝直接控制“上三旗”的制度。
八旗分为满洲八旗、蒙古八旗和汉军八旗，每旗均设都统，归中央八旗都统衙门统管，地方督抚无权征调。
八旗军分为守卫京师的“禁卫兵”和驻防地方的“驻防兵”。
禁卫兵又分郎卫和兵卫。
郎卫选上三旗中才武出众者组成，分班人值禁中宿卫，由领侍卫内大臣统领。
兵卫建制有：八旗骁骑营、八旗前锋营、八旗护军营、八旗步军营、内府三旗、火器营、健锐营、虎枪营。
驻防兵则根据驻防地的轻重，确定驻兵人数的多寡和统领武职官员品秩的高低，有将军、都统、副都统、城守尉、防守尉之别。
大凡各省会、要地均有驻防兵，合满洲、蒙古、汉军旗以为营。
涉及知识点：中国古代史2．论述雅典“伯里克利时代”的民主政治正确答案：希波战争结束之时，雅典政治已经达到古代奴隶制下最民主的程度。
当时担任雅典民主派领袖并执掌政权数十年之久的是伯里克利，故这一时期被称作“伯里克利时代”。
伯里克利为人廉洁奉公、守正不阿，有眼光，善演说，具备一个优秀政治家的品格和气质。
高频电子电路试卷及参考答案 评分标准
XXXXX 大学试卷学年第 一 学期 课号 课程名称 高频电子电路 适用班级（或年级、专业） 信息与通信学院 考试时间 120 分钟 班级 学号 姓名一、单项选择题（每小题2分，共16分）1、高频电子电路中常采用（ ）参数等效电路进行分析。
A 、XB 、YC 、ZD 、S 2、随着级数的增加，多级单调谐放大器（各级的参数相同）的通频带（ ），选择性（ ）。
A 、变大、变好B 、变小、变好C 、变大、变差D 、变小、变差3、高频功放一般采用丙(C)类功放，C 类功放的导通角θ范围为（ ），并且一般情况下θ越小，其效率越（ ）A 、θ>90o 、高B 、θ>90o 、低C 、θ<90o 、高D 、θ<90o 、低4、振荡器是根据（ ）反馈原理来实现的，（ ）反馈振荡电路的波形相对较好。
A 、正、电感B 、正、电容 C、负、电感 D 、负、电容5、设非线性元件的静态特性曲线用下列多项式来表示：i ＝a 0＋a 2u i 2＋a 5u i 5，加在该元件上的电压为：u i ＝2cosω1t ＋5cosω2t (v)，则电流i 中所包含的频谱成份中含有下述频率中的哪些频率成份。
（ ）A 、2ω1＋5ω2和5ω1＋2ω2B 、7ω1和7ω2C 、ω1和ω1＋2ω2D 、4ω1和2ω1＋2ω26、调幅（AM ）波总功率（ ）未调载波功率，调频（FM ）波总功率（ ）未调载波功率。
A 、大于、小于B 、小于、等于C 、等于、等于D 、大于、等于7、用间接调频得到FM 信号中心频率为f 01＝200kHz ，最大频偏Δf m1=30Hz ，则经过500倍频后，中心频率f 02＝100MHz ，最大频偏Δf m2=（ ）Hz 。
若使用混频的办法将其中心频率搬移到100MHz 上时，其最大频偏Δf m3=（ ）Hz 。
A 、30 、30B 、30、15000C 、15000、30D 、 15000、150008、 具有自限幅功能的是（ ）鉴频器。
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2013-2014学年第二学期《高频电子技术》期末试卷(A)姓名：学号：专业班级：一、填空题（每空1分，共20分）1.并联谐振回路中，若外加信号源频率高于LC谐振频率，LC并联后的电抗呈容性。
2.并联谐振回路作为负载时常采用抽头接入的目的是为了减小信号源内阻和负载对回路的影响，若接入系数p增大，则谐振回路的Q值减小，带宽加宽。
3.已知一串联谐振回路的谐振频率为1MHz，回路中的电感L=150μH，电阻R=10Ω，则谐振回路的通频带为10.6 kHz。
4.高频小信号放大器的主要质量指标有：增益、通频带、选择性、工作稳定性和噪声系数。
5.若单级单调谐放大器的增益为10dB，则3级单调谐放大器级联后总的增益为30dB ，通频带是单级通频带的6.三极管混频器的变频增益大于1。
7.如果一个高频功放处于临界状态，只增加输入信号的振幅，功放会进入过压工作状态；若是在谐振回路两端并联一个电阻R，功放会进入欠压工作状态。
8.某单一频率的载波信号的幅度为4V，对它进行标准幅度调制，已调波的最大振幅为m为0.5 。
6V，则调幅系数a9.为了有效地实现集电极调幅，调制器必须工作在过压状态；为了有效地实现基极调幅，调制器必须工作在欠压状态。
10.二极管包络检波只适用解调标准调幅信号，对于DSB、SSB信号解调则需采用同步检波电路，它要求接收端载波与发送端载波同频、同相。
二、单项选择题（每题只有1个正确答案,每题1分，共5分）1．欲提高功率放大器的效率，应使放大器的工作状态为（ D ）A．甲类B．乙类C．甲乙类D．丙类2．以下几种混频器电路中，输出信号频谱最纯净的是（ B ）A．二极管平衡混频器B．模拟乘法器混频器C．二极管环形混频器D．三极管混频器3．属于频谱的非线性搬移过程的有（ D ）A．振幅调制B．调幅波的解调C．混频D．频率调制4．利用石英晶体的电抗频率特性构成的振荡器是（B ）f=f时，石英晶体呈感性，可构成串联型晶体振荡器A．qf=f时，石英晶体呈阻性，可构成串联型晶体振荡器B．qf<f<f时，石英晶体呈阻性，可构成串联型晶体振荡器C．p qf<f<f时，石英晶体呈感性，可构成串联型晶体振荡器D．q p5．利用非线性器件作用来实现频率变换时，其有用项为（ B ）A．一次方项B．二次方项C．高次方项D．全部项三、问答题（每题6分，共18分）1．什么是调幅，什么是调频，什么是调相？ 答：调幅指的是载波的频率和相角不变，载波的振幅按照调制信号的变化规律变化（2分） 调频指的是载波振幅不变，载波的瞬时频率按照调制信号的变化规律变化（2分） 调相指的是载波振幅不变，载波的瞬时相位按照调制信号的变化规律变化（2分）2．高频功率放大器原来工作在临界状态，如果集电极回路稍有失谐，功放的工作状态会如何变化？ 0c I ，1cm I ，0P ，c P 将如何变化？答：回路谐振时，回路等效阻抗为纯阻，且最大，当回路失谐时，回路等效阻抗减小，放大器将从临界状态变为欠压状态。
（2分）0c I 不变（1分）1cm I 不变（1分）0P 减小（1分）c P 增大（1分）3．在反馈型LC 振荡器中，起振条件是什么？平衡条件是什么？起振时放大器的工作状态与平衡时的工作状态有何不同？振荡起振条件与平衡条件中放大倍数A 是否相同？答：起振条件是10>∙∙F A （1分）；平衡条件是1=∙∙F A （1分）；起振时放大器工作在线性状态（1分）；平衡时工作在非线性状态（1分）；起振条件中的放大倍数A 大于平衡条件中放大倍数A 。
（2分）四、判断题（共17分）1. （每题3分，共12分）在振幅条件已满足的前提下，用相位条件去判断下列各图所示振荡器的交流等效电路中，哪些不可能振荡？哪些有可能振荡？对于那些可能振荡的电路，说明在什么条件下才能振荡（如果不需要任何条件则不用说明），并注明它属于哪种类型的振荡器。
不能振荡（3分）C1C2C3L3可能振荡（2分）电感反馈式三端振荡器（1分）注：(a)为抽头变换前；(b) 为抽头变换后[本小问共3分，（a ）与（b ）图只要画出一个即可，但如果抽头次序错误则扣1分。
少画1个元件扣0.5分，扣完3分为止。
]（2）5.020*******===N N p （0.5分），25.020541212===N N p （0.5分）又pF L C C L 35.10102)10352(1116261420140=⨯⨯⨯⨯==∴=-∑∑πωω （1分） pF C p C p C C ie oe 27.81025.08.55.035.10222221=⨯-⨯-=--=∴∑（1分）（3）)(7.221001021035211660140uS Q L G p =⨯⨯⨯⨯⨯==-πω )(36.0102.325.01055.05.0105.45323262221mS g p g p G g ie oe p =⨯⨯+⨯⨯+⨯=++=∴---∑（1分）4.181036.0105325.05.0||||33210=⨯⨯⨯⨯==∴--∑g y p p A fe v （1分）又3.61036.010*******1366140=⨯⨯⨯⨯⨯⨯==--∑πωg L Q L （1分）)(5.53.610352607.0MHz Q f f L =⨯==∆∴（1分） 2、解：（1）若要获得最大输出功率，功放管应调整在临界状态（1分）。
)(8.10129.0V V V cc cm =⨯==ξ（1分）)(8.104.528.102202Ω=⨯==P V R cm p （1分）（2）()()()%7627.0455.09.021*******=⨯⨯===c c c c g θαθαξθξη（2分）W P P P P P cc 7.14.576.04.5000=-=-=-==η（1分） （3） 若负载电阻减小一半，则功放将工作在欠压状态。
从临界到欠压状态，1cm I 几乎不变（1分）。
1cm p cm I R V =将减小一半（1分）。
所以cm cm V I P 1021=将减小一半，变为2.7W （1分）。
若负载电阻增大一倍，则功放将工作在过压状态。
从临界到过压状态，cm V 几乎不变（1分）。
pcmcm R V I =1将减小一半（1分）。
所以cm cm V I P 1021=将减小一半，变为2.7W （1分）。
3、解：（1）将t t v v v ππ20000cos 2000cos 21+=+=代入2510v v i ++=并展开得tt t t t t t t t t t t i ππππππππππππ40000cos 5.022000cos 18000cos 4000cos 5.020000cos 52000cos 511)20000(cos 20000cos 2000cos 2)2000(cos 20000cos 52000cos 51022++++++=+++++=（2分）可见输出共有7个频率分量，其频率和振幅分别为：直流分量（11mA ）、1kHz 分量（5mA ）、2kHz 分量（5mA ）、9kHz 分量（1mA ）、10kHz 分量（5mA ）、11kHz 分量（1mA ）、20kHz 分量（0.5mA ）（3.5分，每个分量0.5分）（2）将上式中的9,10,11kHz 分量滤出整理得t t ππ20000cos )2000cos 4.01(5+可见有调幅作用，且是一个调幅度为0.4的AM 调幅波（2.5分）（3）可以当作混频器(1分)，输出和频分量11kHz 振幅为1mA (1分)4A 、解：（1）0ω=2610⨯π 30=V V100021⨯=Ωπ 3.01=a m45.033.0212101=⨯⨯=V m a 100042⨯=Ωπ 5.02=a m 75.035.0212102=⨯⨯=V m a频率分量及幅度为：()2000102620-⨯=Ω-πω 75.0()1000102610-⨯=Ω-πω 45.0 60102⨯=πω 3()1000102610+⨯=Ω+πω 45.0()2000102620+⨯=Ω+πω 75.0（2） W=1000822⨯=Ωπ（即4kHz ）（2分） （3）)(5.41232220W R V P OT =⨯==（2分）)(765.05.45.0215.43.021*******221)(W P m P m P OT a OT a =⨯⨯+⨯⨯=+=Ω±ω（2分）所以)(265.5765.05.4)(W P P Po O T =+=+=Ω±ω（1.5分）4B 、解：（1） 调频指数6.0=f m ；(1分)最大频偏)(60010006.0max Hz F m f f =⨯=∙=∆（2分）f(Khz1000 999 1001998 1002 频谱图(2.5分)画错1根扣0.5分（2） 由卡森公式)(32001000)16.0(2)1(2Hz F m BW f =⨯+⨯=+=（2分）（3） )(5.413212122W R A P =⨯==（2分） （4） 根据调频波的调制指数公式Ω=ΩV k m f f ，可列方程ππ20002006.0Ω⨯=V ，（1分）故可得调制信号振幅)(6V V =Ω，故调制信号表达式为))(2000cos(6V t π（2分）。