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第四周国旗下讲话范文
同学们：3月12日是我国的植树节。为什么要规定这个节日呢？因为春季是植树造林的好季节，花草树木和人类生活息息相关，植树造林是绿化祖国，美化环境的一件大事。植树造林能调节气候，保持水土，防止和减轻旱涝、风沙等自然灾害。我国历史上曾是个森林资源丰富的国家，辽阔的国土上遍布着茂密的森林。但是由于历史上无数次的战争，历代封建统治者大兴土木乱砍乱伐，由于农业的发展和人口增长而发生的大规模毁林开荒，加上帝国主义的掠夺等原因，我国的森林面积大大缩小了。到全国解放时，我国的森林覆盖（森林面积占土地面积的百分比）只8%左右。森林的破坏给自然和人类带来了严重后果。例如，黄河中游地区，由于树木稀少，荒山荒地丧失截留雨水能力，土壤侵蚀严重，河床不断淤塞增高，经常泛滥成灾，解放前的2500多年里，黄河决口1500多次。黄河每年输往下游的泥沙约16亿吨。黄河流域、长江流域，每年至少有 600万亩以上的沃土被冲进大海。由于缺乏足够的森林来调节气候，也使得旱灾不断发生。据统计，清明268年间，就有201次旱灾发生。
第八周国旗下讲话范文
同学们、老师们、早上好！今天国旗下讲话的主题：在春天起跑，做文明新人。同学们，在生活当中，你们扮演着不同的角色，有着不同的身份。对老师来说，你们是学生；对父母来说，你们是儿女，对国家来说，你们是一位小公民。你们的身上寄托着老师、父母、祖国的希望。作为一位光荣的小公民，我们怎样才能做到“尊师守纪，文明有礼，从小立志，学会做人”呢？首先，我们要树立信念，勤奋学习、学会学习，全面发展。最近有人提出了一个“知识折旧论”，即一年不学习，你拥有的全部知识将折旧80%。因此，终身学习是知识经济时代的成功之本。由此可见，学习是终身大事，而老师却不可能伴你终身。因此，大家要主动学习，学会学习，掌握学习的技巧。懂得“点石成金”的“法术”，做到“好学、会学、乐学”。只有从小就播下自主成功的“希望种子”。才能踏上成功的阶梯。
第11周国旗下讲话范文
用良好的行为习惯塑造优秀的品质良好的行为习惯能逐步铸就优秀的品质，那作为元通小学的学生，我们应该怎样才能够培养良好的行为习惯，塑造优秀的品质呢？第一、我们要正确认识培养良好的行为习惯的重要性与艰巨性我们都知道，有良好的学习习惯的同学，上课时他能够认真听讲，课后他能及时保质地完成老师布置的作业，别人玩耍时他能认真学习、静心地看书，他能自己掌握老师所没有讲过的许多知识。而有的同学，老师上课时他东插嘴西扯蛋，老师布置的任务迟迟不能完成。这些坏习惯的存在，导致他的成绩与前一种同学有天壤之别，据心理学家的研究表明：一千个人里面只有三个人的智力是超群的，同样也只有三个人的智力是有障碍的。也就是说我们每个班一班同学的智商都是不相上下的，只是我们有的同学养成了良好的行为习惯，所以优秀，有的同学则学会了一些坏的毛病，所以落后，所以受人批评。只要你意识到了这一点，逐步改正毛病并养成良好的行为习惯，那么我们每个人都可以成为优秀的学生，你愿意吗？
端午节国旗下讲话作文
端午节国旗下讲话小学(一)端午节是古老的传统节日，始于中国的春秋战国时期，至今已有XX多年历史。据《史记》记载，屈原，是春秋时期楚怀王的大臣。他倡导举贤授能，富国强兵，力主联齐抗秦，遭到贵族强烈反对，屈原去职，被赶出成都，流放到沅.湘流域。他在流放中，写下了忧国忧民的《离骚》.《天问》.《九歌》等不朽诗篇等，独具风貌，影响深远(因而，端午节也称诗人节)。公元前278年，秦军攻破楚国京都。屈原眼看自己的祖国被侵略，心如刀割，但是始终不忍舍弃自己的祖国，于五月五日，在写下了绝笔作《怀沙》之后，抱石投汨罗江身死，以自己的生命谱写了一曲壮丽的爱国主义乐章。传说屈原死后，楚国百姓哀痛异常，纷纷涌到汨罗江边去凭吊屈原。渔夫们划起船只，在江上来回打捞他的真身。有些渔夫拿出为屈原准备的饭团.鸡蛋等食物丢进江里，说是让鱼龙虾蟹吃饱了，就不会去咬屈大夫的身体了。人们见后纷纷效仿。后来因为怕饭团为蛟龙所食，人们想出用楝树业包饭，外缠彩丝，发展成粽子。以后每年5月5日定位端午节。端午节，门查艾.香满堂.吃粽子.洒白酒.龙舟下水喜洋洋，这些，都是曾经在端午节上最热闹的活动。
雷锋日国旗下讲话稿范文
尊敬的各位老师,同学们：大家早上好,今天我国旗下讲话的题目是《做新时代的雷锋》.绿色的三月微笑着向我们走来，在这令人感动的季节里，对于离开雷锋时代已46个春秋的我们而言，只能从传颂中认识他，在我的印象中，雷锋有一张永远洋溢着青春气息的笑脸，是一个乐于助人，大公无私，舍己为人的青年，他说：“一个人的生命是有限的，可为人民服务却是无限的，他说到了也做到了.我想他那灿烂的笑容就是来自为人民的快乐，是一种发自内心的满足。雷锋走了，但他的精神体现着人中至善的一面，因而他赢得了世人的尊重，学习雷锋，不是一个口号，更不是一个形式，而是一个个鲜国旗下讲话活的事例在生活中现，当我们受挫时，身边的你一个鼓励的微笑，让我们重新鼓起了勇气，跌倒时，你伸出援助之手拉我们一把，我们明白你一直在支持着我们。这些都不是什么惊天动地的壮举，但却感动着我们，这或许也是雷锋精神的一种吧!这样的精神让我们感受到了一种人文的关爱。
新一年销售工作计划怎么写
一、改变思维，快速推广品牌我是公司的一名白酒销售业务员，对于我们公司这个品牌来说，我们做业务员的理当是有非常足的底气的。所以在做业务的时候，我们一定不要忘记对我们品牌的一个推广。我们平时在做业务的过程中，只记得怎么将产品推出去，却没有想过推出去之后是否还有第二次推出去的可能，是否还可以将这一份努力产生两份成果等等。这些我们平时工作的时候可能都会忘记，也可能会被我忽略掉。所以以后做业务的时候我会及时的调整方针，也会在这份激情之上安放一份沉稳，好好的工作，努力的工作。
XX街道2024年第一季度工作总结
三、守牢底线狠抓安全，平安建设持续向稳紧抓安全不松懈。我们始终把“稳”字贯穿平安建设工作全过程，针对交通事故频发，金华挂牌督办的问题，今年来我们开展交通安全综合治理大会战，成立交通安全综合治理领导小组，设立工作专班，聘用专兼职交通劝导员40余人，各村社设立劝导点位22个，全力以赴推进交通安全综合治理工作。在安全生产方面，我们建立安全生产研判例会机制，每周不少于3次分领域研判安全生产工作情况，对于存在的问题及隐患风险点，逐个研究整改举措，街道班子逐人包案督促落实，全力以赴保障安全生产形势持续稳定。坚持安全生产督导常态化，针对街道现存“一厂多租”、泡沫行业等48家规上企业、114家归下企业，以及363幢出租房和470个沿街店面，修订完善街道干部包联制度，形成“三个一”工作机制。
街道2024年第一季度工作总结
紧抓安全不松懈。我们始终把“稳”字贯穿平安建设工作全过程，针对交通事故频发，金华挂牌督办的问题，今年来我们开展交通安全综合治理大会战，成立交通安全综合治理领导小组，设立工作专班，聘用专兼职交通劝导员40余人，各村社设立劝导点位22个，全力以赴推进交通安全综合治理工作。在安全生产方面，我们建立安全生产研判例会机制，每周不少于3次分领域研判安全生产工作情况，对于存在的问题及隐患风险点，逐个研究整改举措，街道班子逐人包案督促落实，全力以赴保障安全生产形势持续稳定。坚持安全生产督导常态化，针对街道现存“一厂多租”、泡沫行业等48家规上企业、114家归下企业，以及363幢出租房和470个沿街店面，修订完善街道干部包联制度，形成“三个一”工作机制，即（一名街道包联干部、一份安全生产大排查大整治检查表、一张体检站整改问题清单），逐企、逐屋、逐个店面开展风险隐患大排查，坚持清单化推进、闭环式整改，确保风险隐患消除不留遗漏，目前共发现问题3361项目，整改完成2869项，累计拆除违法建筑面积15340平方米。
工业园区2024年一季度工作总结
结合**市2024年招才引智双选会,“千校万岗就业有位来”全区企业进校园专场招聘会,**县2024年“春风行动”暨就业援助月专场招聘会,征集岗位1188个。深入开展2024年工程研究中心人才奖补项目、自治区领军人才培养项目、自治区“塞上卓越”工程师等项目,强化人才政策落实,2人成功申领创新型大学生共有产权房,园区尊才爱才重才氛围日益浓厚。五、守红线,筑底线,园区环境平稳绿色。严守安全红线和环保底线,以“时时放心不下”的责任感,始终保持睁眼睡觉的警觉、如履薄冰的警惕,扛牢安全生产责任,狠抓安全生产各项措施落实和各类反馈问题整改,精准管控重点行业领域安全风险,抓实抓细抓好抓牢抓严园区安全生产工作。树牢绿水青山就是金山银山理念,严把项目准入门槛,强化环保督导督查,巩固中央、区市环保督察和“回头看”反馈问题整改成果,积极引导园区现有企业转变发展方式实现绿色转型,全力打造安全绿色生态的发展环境。
2024年第一季度工作总结汇编（32篇）
按照“谁起草、谁审查”的原则，结合工作实际，我局制定下发了《XX市XX区司法局关于关于在市场体系建设中建立公平竞争审查制度的通知》,并要求局属各部门负责本部门出台政策措施的公平竞争审查和合法性审查工作，在起草文件过程中严格对照《XX市XX区人民政府办公室关于在市场体系建设中建立公平竞争审查制度的通知》（晋政办通〔2017〕138号）要求中的内容，就审查对象、标准和要求进行严格审查。确保我局制定的有关政策措施符合公平竞争和相关法律法规要求，防止出现排除、限制竞争的情况。二、有序开展自查清理工作根据自查清理工作要求，我局认真对发文进行重点审查，对已出台的政策文件，严格进行自我审查。经清理，我局一季度未出台过涉及市场主体经济活动的规章、规范性文件、其他政策措施等。三、工作亮点
新人教版高中英语必修3Unit 1 Festivals and celebrations-Discovering Useful Structure教学设计
4.That was an experience that frightened everyone. →That was _____________________. 答案：1. taking 2. being discussed 3. in the reading room 4. a frightening experienceStep 6 The meaning and function of V-ing as the predicative动词-ing形式作表语，它通常位于系动词后面，用以说明主语“是什么”或“怎么样”一种表示主语的特质、特征和状态, 其作用相当于形容词; 另一种具体说明主语的内容, 即主语等同于表语, 两者可互换。The music they are playing sounds so exciting. 他们演奏的音乐听起来令人激动。The result is disappointing. 结果令人失望。Our job is playing all kinds of music. 我们的工作就是演奏各种音乐。Seeing is believing. 眼见为实。Step 7 Practice1. It is ________(amaze) that the boy is able to solve the problem so quickly.2. Buying a car is simply _______(waste) money. 3. Please stop making the noise—it’s getting ________(annoy). 4. complete the passage with the appropriate -ing form.La Tomatina is a festival that takes place in the Spanish town Bunol every August. I think many food festivals are __________ because people are just eating. however, this festival is _________ because people don't actually eat the tomatoes. Instead, they throw them at each other! the number of people ________ part in this tomato fight, can reach up to 20,000, and it is a very __________ fight that lasts for a whole hour. The _______ thing is how clean Bunol is after the tomatoes are washed away after the fight. this is because the juice form tomatoes is really good for making surfaces clean!答案：1. amazing 2. wasting 3. annoying4. boring interesting taking exciting amazing
新人教版高中英语必修3Unit 1 Festivals and Celebrations-Reading and Thinking教学设计
The topic of this part is “Discover the reasons for festivals and celebrations.The Listening & Speaking & Talking part aims at talking about the experiences and feelings or emotions about the festivals and celebrations. This section aims at detecting the reason why the people celebrate the festivals, the time, the places, the types and the way of celebrations. It also explains why some traditions in the old celebrations are disappearing, like the firecrackers in the big cities and some new things are appearing like the prosperity of business or commerce. 1. Students can talk about what festivals they know and the reasons and the way of celebrating them.2. Students should learn the reading skills such as the headline and get the topic sentences, the structures of articles.3. Students can understand the past, the present situation of some festival around the world and why there are some changes about them. 4. Students can have the international awareness about the festivals.1. Students should learn the reading skills such as the headline and get the topic sentences, the structures of articles.2. Students can understand the past, the present situation of some festival around the world and why there are some changes about them.Step 1 Lead in---Small talkWhat festival do you like best ? Why ?I like the Spring Festivals because I can set off the fireworks, receive the lucky money and enjoy the Gala with my families.Step 2 Before reading---Pair workWhy do people celebrate different festivals ?The Spring Festivals is to celebrate the end of winter and the coming of spring and new life.The Mid-autumn Day is to celebrate the harvest and admire the moon.
新人教版高中英语必修3Unit 1 Festivals and Celebrations-Listening &Speaking＆Talking教学设计
The theme of this section is “Talk about festival activities and festival experiences”.Festival and holiday is a relaxing and interesting topic for students. This part talks about the topic from the daily life of students’. In the part A ---Listening and Speaking, there are three conversations among different speakers from three countries(Japan, Rio and China), where the speakers are participating in or going to participate in the festivals and celebrations. So listening for the relationship among them is a fundamental task. Actually, with the globalization and more international communication, it is normal for Chinese or foreigners to witness different festivals and celebrations in or out of China. In the Conversation 1, a foreign reporter is interviewing a Japanese young girl who just had participated in the ceremony of the Coming-of-Age Day on the street and asking her feeling about the ceremony and the afterwards activities. Conversation 2, Chinese girl Li Mei is witnessing the Rio Carnival for the first time, and her friend Carla gives her some advice on the costumes which enables her to match with the carnival to have a good time. Conversation 3, a Chinese guide is showing a group of foreign visitors around the Lantern Festival and introducing the customs of the festival to them. The three conversations have a strong vitality and insert the festival and cultural elements from different countries. So perceiving the festivals and cultures from different countries is the second task. At the same time, the scripts also insert the targeted grammar --- v-ing as attributive and predicative, which students can perceive and experience in a real context and make a road for the further study. That is the third task. In the Part B--- Listening and Talking, the theme is “Talk about festival experience”, which is the common topic in our daily conversations. During the conversation, Song Lin, a Chinese student, asked Canadian friend Max about how to spend Christmas. In the conversation, Song Lin talked about experience and the feelings during the Chinese Spring Festival, during which there are not only some enjoyable things but some unpleasant things. After the listening, perhaps students find there are some similarities between Christmas and the Chinese Spring Festival as there are some differences in the origins and celebrations. For example, people always visit friends and relatives, decorate their houses, have a big dinner together, chat and give presents to each other.
新人教版高中英语必修3Unit 1 Festivals and Celebrations-Reading for writing教学设计二
Step 3 Analyzing article structureActivity 31. Teachers raise questions to guide students to analyze the chapter structure of this diary and think about how to describe the festival experience. (1)What should be included in the opening/body/closing paragraph(s)?(2)How did the writer arrange his/her ideas?(3)What kind of interesting details did the writer describe?(4)How did the writer describe his/her feelings/emotions during the event?2. Students read and compare the three sentence patterns in activity 2. Try to rewrite the first paragraph of the diary with these three sentence patterns. After that, students exchange corrections with their partners. Such as:●This was my first time spending three days experiencing the Naadam Festival in China’s Inner Mongolia Autonomous Region and it was an enjoyable and exciting experience. ●I'll never forget my experience at the Naadam Festival because it was my first time to watch the exciting Mongolian games of horse racing, wrestling, and archery so closely. ●I'll always remember my first experience at the Naadam Festival in China’s Inner Mongolia Autonomous Region because it was so amazing to spend three days witnessing a grand Mongolian ceremony. Step 4 Accumulation of statementsActivity 41. Ask the students to read the diary again. Look for sentences that express feelings and emotions, especially those with the -ing form and the past participle. Such as:● …horse racing, wrestling, and archery, which are all so exciting to watch. ● some amazing performances● I was surprised to see…● I was a little worried about. . . ● feeling really tiredOther emotional statements:●I absolutely enjoyed the archery, too, but the horse races were my favourite part. ●I'm finally back home now, feeling really tired, but celebrating Naadam with my friend was totally worth it. ●He invited me back for the winter to stay in a traditional Mongolian tent and cat hot pot. I can’t wait!2. In addition to the use of the -ing form and the past participle, the teacher should guide the students in the appreciation of these statements, ask them to memorize them, and encourage them to use them reasonably in writing practice.
新人教版高中英语选修2Unit 1 Science and Scientists-Discovering useful structures教学设计
The grammatical structure of this unit is predicative clause. Like object clause and subject clause, predicative clause is one of Nominal Clauses. The leading words of predicative clauses are that, what, how, what, where, as if, because, etc.The design of teaching activities aims to guide students to perceive the structural features of predicative clauses and think about their ideographic functions. Beyond that, students should be guided to use this grammar in the context apporpriately and flexibly.1. Enable the Ss to master the usage of the predicative clauses in this unit.2. Enable the Ss to use the predicative patterns flexibly.3. Train the Ss to apply some skills by doing the relevant exercises.1.Guide students to perceive the structural features of predicative clauses and think about their ideographic functions.2.Strengthen students' ability of using predicative clauses in context, but also cultivate their ability of text analysis and logical reasoning competence.Step1: Underline all the examples in the reading passage, where noun clauses are used as the predicative. Then state their meaning and functions.1) One theory was that bad air caused the disease.2) Another theory was that cholera was caused by an infection from germs in food or water.3) The truth was that the water from the Broad Street had been infected by waste.Sum up the rules of grammar:1. 以上黑体部分在句中作表语。2. 句1、2、3中的that在从句中不作成分，只起连接作用。 Step2: Review the basic components of predicative clauses1.Definition
新人教版高中英语选修2Unit 1 Science and Scientists-Learning about Language教学设计
Step 7: complete the discourse according to the grammar rules.Cholera used to be one of the most 1.__________ (fear) diseases in the world. In the early 19th century, _2_________ an outbreak of cholera hit Europe, millions of people died. But neither its cause, 3__________ its cure was understood. A British doctor, John Snow, wanted to solve the problem and he knew that cholera would not be controlled _4_________ its cause was found. In general, there were two contradictory theories 5 __________ explained how cholera spread. The first suggested that bad air caused the disease. The second was that cholera was caused by an _6_________(infect) from germs in food or water. John Snow thought that the second theory was correct but he needed proof. So when another outbreak of cholera hit London in 1854, he began to investigate. Later, with all the evidence he _7_________ (gather), John Snow was able to announce that the pump water carried cholera germs. Therefore, he had the handle of the pump _8_________ (remove) so that it couldn't be used. Through his intervention，the disease was stopped in its tracks. What is more, John Snow found that some companies sold water from the River Thames that __9__________________ (pollute) by raw waste. The people who drank this water were much more likely _10_________ (get) cholera than those who drank pure or boiled water. Through John Snow's efforts, the _11_________ (threaten) of cholera around the world saw a substantial increase. Keys： 1.feared 2.when 3. nor 4.unless 5.that/which 6.infection 7.had gathered 8.removed 9.was polluted 10.to get 11. threat
新人教版高中英语选修2Unit 1 Science and Scientists-Reading and thinking教学设计
Step 5： After learning the text, discuss with your peers about the following questions:1.John Snow believed Idea 2 was right. How did he finally prove it?2. Do you think John Snow would have solved this problem without the map?3. Cholera is a 19th century disease. What disease do you think is similar to cholera today?SARS and Covid-19 because they are both deadly and fatally infectious, have an unknown cause and need serious public health care to solve them urgently.keys:1. John Snow finally proved his idea because he found an outbreak that was clearly related to cholera, collected information and was able to tie cases outside the area to the polluted water.2. No. The map helped John Snow organize his ideas. He was able to identify those households that had had many deaths and check their water-drinking habits. He identified those houses that had had no deaths and surveyed their drinking habits. The evidence clearly pointed to the polluted water being the cause.3. SARS and Covid-19 because they are both deadly and fatally infectious, have an unknown cause and need serious public health care to solve them urgently.Step 6: Consolidate what you have learned by filling in the blanks:John Snow was a well-known _1___ in London in the _2__ century. He wanted to find the _3_____ of cholera in order to help people ___4_____ it. In 1854 when a cholera __5__ London, he began to gather information. He ___6__ on a map ___7___ all the dead people had lived and he found that many people who had ___8____ (drink) the dirty water from the __9____ died. So he decided that the polluted water ___10____ cholera. He suggested that the ___11__ of all water supplies should be _12______ and new methods of dealing with ____13___ water be found. Finally, “King Cholera” was __14_____.Keys: 1. doctor 2. 19th 3.cause 4.infected with 5.hit 6.marked 7.where 8.drunk 9.pump 10.carried 11.source 12.examined 13.polluted 14.defeatedHomework: Retell the text after class and preview its language points
新人教版高中英语选修2Unit 1 Science and Scientists-Using langauge教学设计
This happens because the dish soap molecules have a strong negative charge, and the milk molecules have a strong positive charge. Like magnets, these molecules are attracted to each other, and so they appear to move around on the plate, taking the food coloring with them, making it look like the colors are quickly moving to escape from the soap.Listening text:? Judy: Oh, I'm so sorry that you were ill and couldn't come with us on our field trip. How are you feeling now? Better?? Bill: Much better, thanks. But how was it?? Judy: Wonderful! I especially liked an area of the museum called Light Games.it was really cool. They had a hall of mirrors where I could see myself reflected thousands of times!? Bill: A hall of mirrors can be a lot of fun. What else did they have?? Judy: Well, they had an experiment where we looked at a blue screen for a while, and then suddenly we could see tiny bright lights moving around on it. You'll never guess what those bright lights were!? Bill: Come on, tell me!? Judy: They were our own blood cells. For some reason, our eyes play tricks on us when we look at a blue screen, and we can see our own blood cells moving around like little lights! But there was another thing I liked better. I stood in front of a white light, and it cast different shadows of me in every color of the rainbow!? Bill: Oh, I wish I had been there. Tell me more!? Judy: Well, they had another area for sound. They had a giant piano keyboard that you could use your feet to play. But then, instead of playing the sounds of a piano, it played the voices of classical singers! Then they had a giant dish, and when you spoke into it, it reflected the sound back and made it louder. You could use it to speak in a whisper to someone 17 meters away.? Bill: It all sounds so cool. I wish I could have gone with you? Judy: I know, but we can go together this weekend. I'd love to go there again!? Bill: That sounds like a great idea!
人教版高中数学选择性必修二等比数列的概念 (1) 教学设计
新知探究我们知道，等差数列的特征是“从第2项起，每一项与它的前一项的差都等于同一个常数” 。类比等差数列的研究思路和方法，从运算的角度出发，你觉得还有怎样的数列是值得研究的？1.两河流域发掘的古巴比伦时期的泥版上记录了下面的数列:9,9^2,9^3,…,9^10; ①100,100^2,100^3,…,100^10; ②5,5^2,5^3,…,5^10. ③2.《庄子·天下》中提到：“一尺之锤，日取其半，万世不竭.”如果把“一尺之锤”的长度看成单位“1”，那么从第1天开始，每天得到的“锤”的长度依次是1/2,1/4,1/8,1/16,1/32,… ④3.在营养和生存空间没有限制的情况下，某种细菌每20 min 就通过分裂繁殖一代，那么一个这种细菌从第1次分裂开始，各次分裂产生的后代个数依次是2,4,8,16,32,64,… ⑤4.某人存入银行a元，存期为5年，年利率为 r ，那么按照复利，他5年内每年末得到的本利和分别是a(1+r),a〖(1+r)〗^2,a〖(1+r)〗^3,a〖(1+r)〗^4,a〖(1+r)〗^5 ⑥
人教版高中数学选择性必修二等差数列的前n项和公式（1）教学设计
高斯（Gauss，1777－1855），德国数学家，近代数学的奠基者之一. 他在天文学、大地测量学、磁学、光学等领域都做出过杰出贡献. 问题1：为什么1＋100＝2＋99＝…＝50＋51呢？这是巧合吗？试从数列角度给出解释.高斯的算法：（1+100）+（2+99）+…+(50+51)= 101×50=5050高斯的算法实际上解决了求等差数列：1，2，3，…，n，"… " 前100项的和问题.等差数列中，下标和相等的两项和相等.设 an＝n，则 a1＝1，a2＝2，a3＝3，…如果数列{an} 是等差数列，p，q，s，t∈N*，且 p＋q＝s＋t，则 ap＋aq＝as＋at 可得：a_1+a_100=a_2+a_99=?=a_50+a_51问题2： 你能用上述方法计算1＋2＋3＋… ＋101吗？问题3： 你能计算1＋2＋3＋… ＋n吗？需要对项数的奇偶进行分类讨论.当n为偶数时， S_n=(1+n)+[(2+(n-1)]+?+[(n/2+(n/2-1)]=(1+n)+(1+n)…+(1+n)=n/2 (1+n) =(n(1+n))/2当n为奇数数时， n－1为偶数
