2017年12月17日托福写作真题解析

2017年考研数学二真题解析

2017年全国硕士研究生入学统一考试数学二试题解析 一、选择题：1～8小题，每小题4分，共32分，下列每小题给出的四个选项中，只有一项符合题目要求的，请将所选项前的字母填在答题纸．．． 指定位置上. （1） ）若函数0(),0x f x b x >=?≤? 在0x =处连续，则（ ） (A)12 ab = (B)12 ab =- (C)0ab = (D)2ab = 【答案】A 【解析】00112lim lim ,()2x x x f x ax a ++→→==Q 在0x =处连续11.22b ab a ∴=?=选A. （2）设二阶可导函数()f x 满足(1)(1)1,(0)1f f f =-==-且'' ()0f x >，则（ ） ()()1 1 110 1 1 1 10()()0 ()0()()()()()A f x dx B f x dx C f x dx f x dx D f x dx f x dx ----><>

2017年12月英语六级考试真题试卷附答案第三卷

2017年12月英语六级考试真题试卷附答案(完整版第3套) Part I Writing (30 minutes) Directions: For this part, you are allowed 30 minutes to write an essay commenting on the saying "Help others, and you will be helped when you are in need." You can cite examples to illustrate your views. You should write at least 150 words but no more than 200 words. ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ Part Ⅰ Writing Be Generous with Your Help When it comes to the topic of help, we are frequently told that, "Help others, and you will be helped when you are in need. '' Simple as the saying is, it implies the importance of helping others in need. What I learn from the remark, in short words, is that helping others is helping yourself. Examples can easily be found to make this point clearer. The story of the ant and the dove is a case in point. An ant slipped into the river when drinking along the river. A dove heard his cries for help and threw him a leaf, which helped the ant float back to the bank. After a few days, a hunter was raising his gun to the dove as she was building her nest. Seeing this, the ant ran quickly to bite the hunter's leg. The dove heard the hunter's scream and flew away. All in all, this example indicates that when we offer our help to others, we are leaving a way open for the future. Helping others is a virtue, and we should take some measures to carry forward this virtue and do others a favor. Only in this way can we build a loving and harmonious society. Part II Listening Comprehension (30 minutes) 说明：由于2017年12月六级考试全国共考了2套听力，本套真题听力与前2套内容完全一样，只是顺序不一样，因此在本套真题中不再重复出现。 Part III Reading Comprehension (40 minutes) Section A 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. Many European countries have been making the shift to electric vehicles交通工具and Germany has just stated that they plan to ban the sale of vehicles using gasoline汽油and diesel柴油as fuel燃料by 2030. The country is also planning to reduce its carbon footprint碳排放by 80-95% by 2050, O26sparking点火、导致 a shift to green energy in the country. Effectively, the ban will include the registration of new cars in the country as they will not allow any gasoline L27powered vehicle to be registered after 2030. Part of the reason this ban is being discussed and H28 implemented is because energy officials see that

2017年考研数学一真题与解析汇总

2017年考研数学一真题 一、选择题 1—8小题．每小题4分，共32分． １．若函数0(),0x f x b x >=?≤? 在0x =处连续，则 （A ）12ab = （B ）1 2 ab =-（C ）0ab =（D ）2ab = 【详解 】0001112lim ()lim lim 2x x x x f x ax ax a +++→→→-===，0lim ()(0)x f x b f -→==，要使函数在0x =处连续，必须满足11 22 b ab a =?=．所以应该选（A ） 2．设函数()f x 是可导函数，且满足()()0f x f x '>，则 （A ）(1)(1)f f >- （B ）11()()f f <- （C ）11()()f f >- （D ）11()()f f <- 【详解】设2()(())g x f x =，则()2()()0g x f x f x ''=>，也就是()2 ()f x 是单调增加函数．也就得到 () ()2 2 (1)(1)(1)(1)f f f f >-?>-，所以应该选（C ） 3．函数22(,,)f x y z x y z =+在点(1,2,0)处沿向量(1,2,2)n =的方向导数为 （A ）12 （B ）6 (C ）4 （D ）2 【详解】 22,,2f f f xy x z x y z ???===???，所以函数在点(1,2,0)处的梯度为()4,1,0gradf =，所以 22(,,)f x y z x y z =+在点(1,2,0)处沿向量(1,2,2)n =的方向导数为 ()01 4,1,0(1,2,2)23f gradf n n ?=?=?=?应该选（D ） ４．甲、乙两人赛跑，计时开始时，甲在乙前方10（单位：米）处，如图中，实线表示甲的速度曲线1()v v t =（单位：米/秒），虚线表示乙的速度曲线2()v v t =（单位：米/秒），三块阴影部分的面积分别为10,20,3，计时开始后乙追上甲的时刻为0t ，则（ ） （A ）010t = （B ）01520t << （C ）025t = （D ）025t > 【详解】由定积分的物理意义：当曲线表示变速直线

2017年12月六级真题第三套

2017年12月大学英语六级考试真题（第3套） Part I Writing (30 minutes) （请于正式开考后半小时内完成该部分，之后将进行听力考试） Directions: For this part, you are allowed 30 minutes to write an essay commenting on the saying "Help others, and you will be helped when you are in need " You can cite examples to illustrate your views. You should write at least 150 words but no more than 200 words. Part II Listening Comprehension (30minutes)说明：由于2017年12月六级考试全国共考了2套听力，本套真题听力与前2套内容完全一样，只是顺序不一样，因此在本套真题中不再重复出现。 Part III Reading Comprehension (40 minutes) Section A 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. Question 26 to 35 are based on the following passage. Many European countries have been making the shift to electric vehicles and Germany has just stated that they plan to ban the sale of vehicles using gasoline and diesel as fuel by 2030. The country is also planning to reduce its carbon footprint by 80-95% by 2050, ___26___ a shift to green energy in the country. Effectively, the ban will include the registration of new cars in the country as they will not allow any gasoline ___27___ vehicle to be registered after 2030. Part of the reason this ban is being discussed and ___28___ is because energy officials see that they will not reach their emissions goals by 2050 if they do not ___29___ a large portion of vehicle emissions. The country is still ___30___ that it will meet its emissions goals, like reducing emissions by 40% by 2020, but the ___31___ of electric cars in the country has not occurred as fast as expected. Other efforts to increase the use of electric vehicles include plans to build over 1 million hybrid and electric car battery charging stations across the country. By 2030, Germany plans on having over 6 million charging stations ___32___. According to the International Business Times, electric car sales are expected to increase as Volkswagen is still recovering from its emissions scandal. There are ___33___ around 155,000 registered hybrid and electric vehicles on German roads, dwarfed by the 45 million gasoline and diesel cars driving there now. As countries continue setting goals of reducing emissions, greater steps need to be taken to have a ___34___ effect on the surrounding environment. While the efforts are certainly not ___35___, the results of such bans will likely only start to be seen by generations down the line, bettering the world for the future. A) acceptance I) incidentally B) currently J) installed C) disrupting K) noticeable D) eliminate L) powered E) exhaust M) restoration F) futile N) skeptical G) hopeful O) sparking H) implemented Section B Directions: In this section, you are going to read a passage with ten statements attached to it. Each statement contains information given in one of the paragraphs. Identify the paragraph from which the information is derived. You may choose a

2017年12月六级仔细阅读真题及解析(卷二)

Passage One Questions 46 to 50 are based on the following passage. You may have heard that Coca-Cola once contained an ingredient capable of sparking particular devotion in consumers: cocaine. The “ coca” in the name referred the extracts of coca leaf that the drinks originator, chemist John Pemberton, mixed with his sugary syrup（姜汁）.At the time, coca leaf extract mixed with wi ne was a com mon tonic（滋补品），and Pembert on ' s sweet brew was a way to get around local laws prohibiting the sale of alcohol. But the other half of the name represents another ingredient, less infamous（名声不好的）,perhaps, but also strangely potent: the kola nut. In West Africa, people have long chewed kola nuts as stimulants, because they contain caffeine that also occurs naturally in tea, coffee, and chocolate. They also have heart stimulants. Historian Paul Lovejoy relates that the cultivation of kola nuts in West Africa is hundreds of years old. The leafy, spreading trees were planted on graves and as part of traditional rituals. Even though the nuts, which need to stay moist, can be somewhat delicate to transport, traders carried them hundreds of miles throughout the forests and grasslands. Europeans did not know of them until the 1500s, when Portuguese ships arrived on the coast of what is now Sierra Leone. And while the Portuguese took part in the trade, ferrying nuts down the coast along with other goods, by 1620, when English explorer Richard Jobson made his way up the Gambia, the nuts were still peculiar to his eyes. By the late 19th century, kola nuts were being shipped by the tonne to Europe and the US. Many made their way into medicines, intended as a kind of energy boost. One such popular medicinal drink was Vin Mariani, a French product consisting of coca extract mixed with red wine. It was created by a French chemist, Angelo Mariani, in 1863. So when Pemberton created his drink,it representedan ongoing trend. When cocaine eventually fell from grace as a beverage ingredient, kola-extract colas became popular. The first year it was available, Coca-Cola averaged nine servings a day across all the Atlanta soda fountains where it was sold. As it grew more popular, the company sold rights to bottle the soda, so it could travel easily. Today about 1.9 billion Cokes are purchased daily. It' s become so iconic that attempts to change its taste in 1985 sweetening it in a move projected to boost sales —proved disastrous, with widespread anger from consumers. -“CoClaocCalassic ,”returned to store shelves just three months after the “New Coke” was released. These days, the Coca-Cola recipe is a closely guarded secret. But it' s said to no longer contain kola nut extract, relying instead on artificial imitations to achieve the flavour. 你可能听说可口可乐曾经含有一种能够使消费者“死忠”的成分：可卡因名中的“ coca”指的是古柯叶的提取物，该饮料的创始人化学家约翰?彭伯顿用它与含糖的姜汁混合在一起。当时，古柯叶提取物与葡萄酒混合是常见的滋补品，而当地法律禁止出售含酒精饮料，彭伯顿的甜饮则避开了该法律。“cola ”代表另一种成分——可乐果：尽管名声不太好，但非常给力。 在西非，人们长期以来一直嚼着可乐果作为兴奋剂，因为它们含有咖啡因。咖啡因在茶、咖啡和巧克力中也天然存在。它们也有心脏兴奋剂。

2017年考研政治真题及解析

2017年考研政治真题及解析（完整版） 一、单项选择题：1～16小题，每小题1分，共16分。下列每题给出的四个选项中，只有一个选项是符合题目要求的。请在答题卡上将所选项的字母涂黑。 1.某地区进入供暖季后，常常出现雾霾。而一旦出现大风天气或等到春暖花开后，雾霾就会散去或减少。从该地区较长时间数据变化看，经过人们努力制霾污染物排放总量在持续降低。但在某些时段，环境空气质量污染指数会迅速攀升，甚至“爆表”。这种看似“矛盾”的现象，凸现了大气污染防治的一个特点。天帮忙极重要，但人们努力才是根本。“人努力”与“天帮忙”直接的关系对我们正确处理主观能动性和客观规律性之间辩证关系的启示是 A.尊重事物的客观规律是正确发挥主观能动性的前提 B.人们有意识的思想活动是掌握客观规律的根本前提 C.认识活动是客观规律性与主观能动性相统一的基础 D.尚未认识的外在自然规律对人的实践活动起着至关重要的作用 【参考答案】A 2.有人认为，既然人的意识是对客观外部世界的反映。那么人脑海里的“鬼”“神”意识就是对外在世界上鬼、神真实存在的反映。这种观念的错误在于 A.夸大了意识的能动作用 B.把意识看成是物质的产物 C.认为意识是对存在的直观反映 D.混淆了人类亦是自然演化的阶段 【参考答案】C 3.某企业投资汽车生产，生产一辆汽车所耗费的生产资料价值为15万元。支付给工人的工资为5万元，假定市场的平均利润率为10%，那么，在自由竞争条件下，该汽车的生产价格是 A.20万元 B.20.5万元 C.21.5万元 D.22万元 【参考答案】D 4.从历史发展的角度看,资本主义生产资料所有制是不断演进和变化的。当今资本主义社会，居主导地位的资本所有制形式是 A.私人资本所有制 B.法人资本所有制 C.私人股份资本所有制 D.垄断资本私人所有制 【参考答案】B 5.从中华人民共和国成立到社会主义改造基本完成是我国从新民主主义到社会主义的过渡时期。这一时期，个体经济向社会主义集体经济过渡的形式是 A.国营经济 B.私人资本主义经济 C.合作社经济 D.国家资本主义经济 【参考答案】C 6.2010年是“十三五”规划开局之年，也是推进供给侧结构性改革的攻坚之年。推进供给侧结构性改革，是适应我国经济发展新常态的重大决策。其根本目的是 A.加快政府职能转变 B.提高供给质量满足需要 C.深化价格、财税、金融、社保等领域基础性改革 D.推进“去产能、去库存、去杠杆、降成本、补短板” 【参考答案】B 7.

2017年12月英语六级第二套阅读真题与答案

2017年12月英语六级第二套阅读真题与答案 Section A 26. I) permit 27. O) territory 28. F) exclusive 29. C) commercial 30. D) communities 31. E) essential 32. G) independent 33. M) sponsor 34. J) secure 35. N) stocks Section B 36. [E] Online services are so designed that the more they are used, the more profit they generate. 37. [L] The author admits using technology as an escape from the task at hand. 38. [I] Checking phones at dinners is now accepted as normal but not belching. 39. [O] To make proper use of technology, we should not only increase our awareness of how it is changing but also how it is impacting us. 40. [B] Most of us find it hard to focus on our immediate tasks because of Internet distractions. 41. [J] When one person starts checking their phone, the others will follow suit. 42. [F] The great majority of smartphone users don’t take the trouble to adjust their settings to suit their own purposes. 43. [D]The Internet is regarded by some as designed to distract our attention. 44. [L] The author attributes his tech addiction chiefly to his habit of putting off doing what he should do right away.

2017年12月六级真题(第一套)

1 2017年12月六级考试真题（第一套） 为了让大家更好地模拟真实考场，文都网校四六级完全按照真题卷面顺序排版了本套真题，Part I 写作部分被放在了试卷的最后一页，与听力部分完全隔开，请大家在备考过程中提早适应卷面顺序！ Part II Listening Comprehension (30minutes)Section A Directions:In this section,you will hear two long conversations.At the end of each conversation,you will hear four questions.Both the conversation 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).Then mark the corresponding letter on Answer Sheet 1with a single line through the centre.Questions 1to 4are based on the conversation you have just heard. 1.A)Host a talk on how to give a good speech. B)Give a lecture on the history of the town. C)Say a few words to thank the speaker. D)Introduce the speaker to the audience. 2.A)He has worked with Miss Bligh for 20years. B)He has published a book on public speaking. C)He was the founder of the local history society.

2017年考研英语二真题及答案解析

2017年考研英语二真题及答案解析 跨考教育英语教研室 Section I Use of English Directions： Read the following text. Choose the best word (s) for each numbered blank and mark A, B, C or D on the ANSWER SHEET. (10 points) People have speculated for centuries about a future without work.Today is no different，with academics，writers，and activists once again 1 that technology is replacing human workers. Some imagine that the coming work-free world will be defined by 2 . A few wealthy people will own all the capital，and the masses will struggle in an impoverished wasteland.. A different and not mutually exclusive 3 holds that the future will be a wasteland of a different sort，one 4 by purposelessness：Without jobs to give their lives 5 ，people will simply become lazy and depressed. 6 today’s unemployed don’t seem to be having a great time. One Gallup poll found that 20 percent of Americans who have been unemployed for at least a year report having depression，double the rate for 7 Americans. Also，some research suggests that the 8 for rising rates of mortality，mental-health problems，and addicting9 poorly-educated middle-aged people is shortage of well-paid jobs. Perhaps this is why many 10 the agonizing dullness of a jobless future. But it doesn’t 11 follow from findings like these that a world without work would be filled with unease. Such visions are based on the 12 of being unemployed in a society built on the concept of employment. In the 13 of work，a society designed with other ends in mind could 14 strikingly different circumstances for the future of labor and leisure. Today，the 15 of work may be a bit overblown. “Many jobs are boring，degrading，unhealthy，and a waste of human potential，” says John Danaher，a lecturer at the National University of Ireland in Galway. These days，because leisure time is relatively 16 for most workers，people use their free time to counterbalance the intellectual and emotional 17 of their jobs. “When I come home from a hard day’s work，I often feel 18 ，” Danaher says，adding，“In a world in which I don’t have to work，I might feel rather different”—perhaps different enough to throw himself 19 a hobby or a passion project with the intensity usually reserved for 20 matters. 1. [A] boasting [B] denying [C] warning [D] ensuring [答案][C] warning 2. [A] inequality [B] instability [C] unreliability [D] uncertainty [答案][A] inequality 3. [A] policy [B]guideline [C] resolution [D] prediction [答案][D] prediction 4. [A] characterized [B]divided [C] balanced [D]measured [答案][A] characterized 5. [A] wisdom [B] meaning [C] glory [D] freedom [答案][B] meaning 6. [A] Instead [B] Indeed [C] Thus [D] Nevertheless [答案][B] Indeed

2017年12月大学英语六级考试真题及答案(第三套)

2017年12月大学英语六级考试真题及答案（第三套）“考试采取“多题多卷”模式，试题顺序不统一，请依据试题进行核对。” Part I Writing (30 minutes) Directions: for this part, you are allowed 30 minutes to write an essay commenting on the saying "Help others,and you will be helped when you are in need "you can cite examples to ilustrate your views. you should write at least 150 words but no more than 200。 Part II Listening comprehension(30miutes) Section a Section a Questions 1 to 4 are based on the conversation you have just heard. 1、a)they forbid business produce more foods than needed b)they facilitate the donation of unsold foods to the needy c)they prohibit the sale of foods that have gone stale d)they reward businesses that eliminate food waste 2、a)it passed a law aiming to stop overproduction b)it prohibited the promotion of bulk food sales c)it voted against food import from outside europe d) imposed penalties on businesses that waste food 3. a)it has penalized businesses that keep overproducing foods b) it has started a nationwide campaign against food waste c) it has warmed its people against possible food shortag d) it has banned supermarkets from dumping edible foods 4. a)americans habit of buying food in bulk. b)a lack of regulation on food consumption.

2017年考研管综真题试题及解析(全套)

2017全国硕士研究生入学统一考试 管理类专业学位联考综合能力试题 一、问题求解（本大题共5小题，每小题3分，共45分）下列每题给出5个选项中，只有一个是符合要求的，请在答题卡上将所选择的字母涂黑。 1、甲从1、 2、3中抽取一个数，记为a ；乙从1、2、 3、4中抽取一个数，记为b ，规定当a b >或者1a b +<时甲获胜，则甲取胜的概率为（ ） （A ）16 （B ）14 （C ）13 （D ）512 （E ）12 【答案】E 【解析】穷举法： 满足a b >的有（2,1）（3,1）（3,2）；满足1a b +<的有（1,3）（1,4）（2,4）； 共六组，因此概率为 61 342 =? 2、已知ABC ?和'''A B C ?满足'''' ::2:3AB A B AC AC ==,',A A π∠+∠=则ABC ?和'''A B C ?的面积比为（ ） （A （B （C ）2:3 （D ）2:5 （E ）4:9 【答案】E 【解析】特值法： 假设2,''''3,'2 AB AC A B A C A A π ====∠=∠= ， 则11 :'22:334:922 S S =????= 3、将6人分成3组，每组2人，则不同的分组方式共有（ ） （A ）12 （B ）15 （C ）30 （D ）45 （E ）90 【答案】B 【解析】分组分配：均匀分组，注意消序 222 642 3 3 15C C C A ??= 4 记123,,σσσ分别为甲、乙、丙投中数的方差，则（ ）

（A ）123σσσ>> （B ）132σσσ>> （C ）213σσσ>> （D ）231σσσ>> （E ）321σσσ>> 【答案】B 【解析】计算方差、比较大小 ()()()()()()()()()222 12 2 2 222 2 3255585=56 3 542454=423 87479714 =73 3 x x x σσσ-+-+-= =-+-+-= =-+-+-= = 甲乙丙，，， 因此，132σσσ>> 5、将长、宽、高分别为12、9、6的长方体切割成正方体，且切割后无剩余，则能切割成相同正方体的最少个数为（ ） （A ）3 （B ）6 （C ）24 （D ）96 （E ）648 【答案】C 【详解】正方体的棱长应是长方体棱长的公约数，想要正方体最少，则找最大公约数即3，因此得到的正方体个数为 1296 24333 ??= 6、某品牌电冰箱连续两次降价10%后的售价是降价前的（ ） （A ）80% （B ）81% （C ）82% （D ）83% （E ）85% 【答案】B 【详解】假设降价前是1，则降价后为()()1110%110%81%?--= 7、甲、乙、丙三种货车载重量成等差数列，2辆甲种车和1辆乙种车的载重量为95吨，1辆甲种车和3辆丙种车载重量为150吨，则甲、乙、丙分别各一辆车一次最多运送货物为（） （A ）125. （B ）120. （C ）115. （D ）110. （E ）105. 【答案】E 【解析】设甲乙丙分别载重量为,,a b c ，由题得 2295337245353150b a c a b a c b b b a c =+?? +=?++==?=??+=? ，因此 所求3105a b c b ++== 8、张老师到一所中学进行招生咨询，上午接到了45名同学的咨询，其中的9位同学下午又咨询了张老师，占张老师下午咨询学生的10%，一天中向张老师咨询的学生人数为（）