山西省总结出了许多重点工矿区的生态环境建设模式,即围绕煤田的露天开采区、居民点和主要交通线建设区,通过工程及生物措施,结合土地的复垦,充分利用厂矿的人力、财力和科技优势,建立集约经营的高效蔬菜、水果及肉蛋奶生产基地(图3.13)。1.说一说图中各种工程及生物措施的作用。点拨:参考图3.13图中各工程及措施的作用:(1)隔离护坝:主要作用是将采掘区与河流隔开,以免河水流入采掘区。(2)排水沟:主要作用是引开可能进入采掘区的雨水或其他水源。(3)公路紧靠采掘区,方便运输车辆就近从工地上公路。(4)“固沙草方格”,即在流沙表面用麦草、稻草扎成1×1米的草方格,使流沙不易被风 吹起,达到阻沙、固沙的目的,并在草方格上栽种沙蒿、花棒、籽蒿、拧条等沙生植物,建立起旱生植物带,营造挡沙树林。
2.通过西气东输输送到上海的天然气,价格只相当于进口天然气的3/4、同等热值煤气的 2/3。你认为是否应该提高天然气的价格,以促进西部的发展。点拨:可以从不同方面分析。⑷对环境的影响①有利于改善东部地区的大气质量据监测显示,在同等热值的情况下,与煤炭相比,利用天然气作燃料几乎不产生二氧化硫、粉尘等污染物质,氮氧化物和二氧化碳的排放量也大为减少。长江三角洲地区的能源长期高度依赖煤炭,例如,上海市煤炭消费量占能源消费总量的70%。从西部地区输送来的天然气,可以部分替代煤炭。②为了最大限度减少对沿线地区生态环境的影响,西气东输工程在建设过程中,严格环境保护的要求。③在沿线农村地区推广使用天然气,可减少农民对薪柴的需求,从而缓解因植被破坏而带来的环境压力。
二、典例解析例3.某公司购置了一台价值为220万元的设备,随着设备在使用过程中老化,其价值会逐年减少.经验表明,每经过一年其价值会减少d(d为正常数)万元.已知这台设备的使用年限为10年,超过10年 ,它的价值将低于购进价值的5%,设备将报废.请确定d的范围.分析:该设备使用n年后的价值构成数列{an},由题意可知,an=an-1-d (n≥2). 即:an-an-1=-d.所以{an}为公差为-d的等差数列.10年之内(含10年),该设备的价值不小于(220×5%=)11万元;10年后,该设备的价值需小于11万元.利用{an}的通项公式列不等式求解.解:设使用n年后,这台设备的价值为an万元,则可得数列{an}.由已知条件,得an=an-1-d(n≥2).所以数列{an}是一个公差为-d的等差数列.因为a1=220-d,所以an=220-d+(n-1)(-d)=220-nd. 由题意,得a10≥11,a11<11. 即:{█("220-10d≥11" @"220-11d<11" )┤解得19<d≤20.9所以,d的求值范围为19<d≤20.9
二、典例解析例10. 如图,正方形ABCD 的边长为5cm ,取正方形ABCD 各边的中点E,F,G,H, 作第2个正方形 EFGH,然后再取正方形EFGH各边的中点I,J,K,L,作第3个正方形IJKL ,依此方法一直继续下去. (1) 求从正方形ABCD 开始,连续10个正方形的面积之和;(2) 如果这个作图过程可以一直继续下去,那么所有这些正方形的面积之和将趋近于多少?分析:可以利用数列表示各正方形的面积,根据条件可知,这是一个等比数列。解:设正方形的面积为a_1,后续各正方形的面积依次为a_2, a_(3, ) 〖…,a〗_n,…,则a_1=25,由于第k+1个正方形的顶点分别是第k个正方形各边的中点,所以a_(k+1)=〖1/2 a〗_k,因此{a_n},是以25为首项,1/2为公比的等比数列.设{a_n}的前项和为S_n(1)S_10=(25×[1-(1/2)^10 ] )/("1 " -1/2)=50×[1-(1/2)^10 ]=25575/512所以,前10个正方形的面积之和为25575/512cm^2.(2)当无限增大时,无限趋近于所有正方形的面积和
课前小测1.思考辨析(1)若Sn为等差数列{an}的前n项和,则数列Snn也是等差数列.( )(2)若a1>0,d<0,则等差数列中所有正项之和最大.( )(3)在等差数列中,Sn是其前n项和,则有S2n-1=(2n-1)an.( )[答案] (1)√ (2)√ (3)√2.在项数为2n+1的等差数列中,所有奇数项的和为165,所有偶数项的和为150,则n等于( )A.9 B.10 C.11 D.12B [∵S奇S偶=n+1n,∴165150=n+1n.∴n=10.故选B项.]3.等差数列{an}中,S2=4,S4=9,则S6=________.15 [由S2,S4-S2,S6-S4成等差数列得2(S4-S2)=S2+(S6-S4)解得S6=15.]4.已知数列{an}的通项公式是an=2n-48,则Sn取得最小值时,n为________.23或24 [由an≤0即2n-48≤0得n≤24.∴所有负项的和最小,即n=23或24.]二、典例解析例8.某校新建一个报告厅,要求容纳800个座位,报告厅共有20排座位,从第2排起后一排都比前一排多两个座位. 问第1排应安排多少个座位?分析:将第1排到第20排的座位数依次排成一列,构成数列{an} ,设数列{an} 的前n项和为S_n。
一、教学目标1.指导学生以一颗真挚的童心、爱心面对大自然,促使学生的心灵与大自然亲切交流。2.使学生明确写景文章的写作范围、写作重点、构思技巧。二、教学重难点明确话题,写景抓住特征,注重感情。三、教学方法多重对话法四、教学过程1.导入语:自然是人类生活的环境,是人类赖以生存的基础。人类不仅在物质上需要大地母亲的哺育,而且在精神上也需要向自然寻求依托。当知时节的春雨飘落大地时,当秋风吹来诱人的果香时,感到喜悦、幸福的决不仅是农民;过去的政治家、文学家,每当失意的时候,就会寄情山林;就是我们中学生,当不堪学习重负,感到身心疲惫的时候,去野外踏青,不也能愉悦身心吗?可以说人对自然的情怀是与生俱来的。但不同的人,对自然的感悟有深浅不同,情趣有高下之分。“万类霜天竞自由”的感悟,“大漠孤烟直”的审美不是人人都能有的。2.面对大自然,通过什么样的手段来促使我们的感悟、审美向高深方向发展呢?哪位同学说说。
1、变换角度,多向思维(多向思维要求思维能针对问题,从不同角度,用多种方法去思考问题。对于作文而言,就是要使学生学会对同一问题,同一素材,同一题目,同一体裁的不同进行区分。)请学生从这则材料中分析出几个角度,准备课堂交流:19世纪法国著名科幻小说家儒勒?凡尔纳,一生写了104部科幻小说。当初他的第一部科幻小说《气球上的星期五》接连被15家出版社退回。他当时既痛苦又气愤,打算将稿子付之一炬。他妻子夺过书稿,给他以鼓励。于是他尝试着走进第16家出版社。经理赫哲尔阅读后,当即表示同意出版,还与儒勒?凡尔纳签订了为期20年的写作出版合同。这则材料叙述时没有一定的中心,属于开发性材料,分析材料中人物、人物关系、故事的不同侧面,可以从不同角度得出结论:
虚构不等于说假话。它是一种源于生活,但高于生活的艺术真实。我们可以举个例子:我国公认的最权威最真实的史书是——《史记》,那么,大家认为《史记》里有没有虚构呢?有。必修一的《鸿门宴》里就有虚构。大家想:司马迁是哪个朝代的人?西汉汉武帝时。刘邦项羽是哪个朝代的?秦末时期。那司马迁不可能坐时光穿梭机到秦末去参加鸿门宴吧?既然他没不在场,那课文《鸿门宴》里人物的语言、动作、甚至是表情从何而来呢?对,是司马迁根据有限的史料加以补充,想象、虚构出来的。那么,同学们在写作文时,也可以不必拘泥于亲身经历的事情,毕竟生活是平淡的,毕竟大家的生活阅历也有限,有时候,我们发挥想象、虚构一个故事来反映生活的真实,也许更生动、也更典型。所以,近年来高考试卷中都提示考生:作文可以大胆想象,编写故事。按照编故事的方式不同,我们的虚构性作文又可以写哪些类型呢:小说,散文,童话,寓言,科幻,故事新编……
据此,研究者认为我国的姓源于原始社会母系氏族时期,并作为一个血缘家族的称号。氏隶属于姓。夏、商、周时期,姓氏作为贵族间区别不同血缘关系的一种制度。自秦汉以后,姓氏不分,合二而一。3、大家有没有听说过《水浒传》中一个人物“西门庆”,他姓西门,为什么姓西门呢?他家住在西门这个地方。大家想想东郭先生为何姓东郭?可见有按居住地而得姓。4、现在如果赋予同学们一个神圣的职责,让你们给一个人赐姓,这个人是杀猪杀鸡杀鸭的,你们觉得要给他一个什么样的姓才合适呢?(自由讨论,姓“屠”)明确:这就是姓氏来源的又一种方法,按照职业取姓。大家想一想有没有其他按照职业得姓的姓氏?(巫、卜、陶等)5、大家通过预习有没有发现其他获得姓氏的方法。(国名、自己祖先的字等。)姓在母系氏族社会以后,逐渐增多,来源极广。主要来源于封国名、谥号、爵位名、官名、居地、职业等。
《贫寒是福天道酬勤石智勇从挫折中奋起》也许是自幼的贫寒生活塑造了石智勇内向的性格,即使是胸挂金灿灿的奖牌接受全场观众欢呼,他的表情也是略显羞涩的。小时候吃不饱肚皮的经历让他至今在“最喜欢的东西”一栏还填写着“食物”二字,而“穷人的孩子早当家”的坚韧,却又是促成他今日辉煌的动力。中国举重队副总教练陈文斌赛后说道:“智勇这几年练得很苦,今天终于有了这样的成绩,这是天道酬勤的结果。石智勇的奥运会金牌是中国男举的一次突破,我们非常激动。”在希腊神话里,命运女神总是让英雄历经磨难。石智勇也不例外。四年前的悉尼奥运会前夕,他在一次训练中扭伤脚踝,失去了参赛机会。“当时我伤心极了,不敢看电视直播,我怕参赛的选手成绩太低了。高点我还好一点,自欺欺人一下说,哎呀好高,自己去了也拿不了冠军,要是低了,自己没去,失去冠军机会,心里痛啊。后来结果出来,也不怎么高,心里真难受。”
4、主旨 哪一联明确地点明全诗题旨?表达了作者的什么感情?试做分析 颈联。 菊花开在秋天,所以这 “ 丛菊 ” 回应了诗题中那个 “ 秋 ” 字。 “ 他日 ” 可以指过去也可以指未来,在这里是指过去。“丛菊两开”,指诗人于 765 年离开成都,原打算很快出峡,但这年留居云安,次年又留居夔州,见到丛菊开了两次,还未出峡,故对菊掉泪。秋菊两度盛开,使诗人再次洒下往日流过的眼泪。“开”字双关,一谓菊花开,又言泪眼随之开。此时他仍然滞留在他乡,他始终没有放弃回乡的打算。孤舟可以系住,使其不能泛诸中流,但诗人的心是系不住的。他的心早已越过江河,越过关山,飞到了长安。所以,一叶靠岸系绳的孤舟,始终都牵动着诗人的故园之思。这一联是全篇诗意所在。孤舟本来只能系住自己的行踪,却把诗人的思乡之心也牢牢地系住了,故见舟伤心,引出故园之思,表现出思乡之情的深沉浓烈和欲归不得的无奈与凄伤,为文章的主旨句。
教学目标:1、了解文学作品解读的个性化及其原因。2、探讨个性化解读遵循的基本原则,合理解读文学作品。教学重点:引导学生关注文学现象,培养他们对文学作品理解的多重思维能力。教学难点:把握个性化的度。避免偏激的理解、过度的张扬所谓个性,严重歪曲文学作品。教学方法:导读、计论、合作探究。教学时间:一课时教学过程:一、创设情境、揭题导入:记得有这样一个故事:一个小孩在四岁就能背《登鹳雀楼》,可平时只有在大人的要求下,他才背出来。直到六岁的某一天,他父母带他去旅游,在他登陆上山顶时,竟然随口背出:“欲穷千里目,更上一层楼”来。这说明了什么?……(讨论)文学作品解读的个性化。二、探讨个性化解读的原因1、读者的差异导致解读的个性化A、同一作品,阅读的时间不同,解读不同。如上面的例子。如《从百草园到三味书屋》和《风筝》主题的多元化理解。“温故知新”,名作重读,不但有趣,而且有益。B、同一作品,不同读者,解读不同。
一、教材1、新教材对高中语文阅读教学的要求高中语文新大纲中明确规定,高中语文教学要让学生“掌握语文学习的基本方法,养成自学语文的习惯”,“为继续学习和终身发展打好基础”,提出了“以阅读教学为龙头带动整个语文教育是一个标本兼治的通途”,以多种渠道培养良好的阅读习惯,以阅读带动听说写能力的全面提高。2、教材分析这篇文章是从美国著名的心理学家、社会学家弗罗姆《爱的艺术》中节选出来的,《爱的艺术》这本书阐释了爱并不是一种与人的成熟程度无关的感情,而是一个能力的问题,是一门通过训练自己的纪律、集中和耐心学到手的一门艺术。在这篇文章中,他从儿童成长的过程的角度阐述了父母之爱与孩童情感与心智成熟的关系,从心理学的角度阐述了爱作为一种改变社会的力量的心理基础。全文10个小节,阐述了一个婴儿成长为一个“成熟的人”其心理结构逐步变化的过程,并在最后指出,真正成熟的人应该能够综合母爱与父爱,唯其如此,才能够使自己真正成为一个健康而成熟的灵魂。
The topic of this part is “Learn to make choices in life”.The Listening & Speaking & Talking part aims at the moral dilemmas, and this part is about making choices in life. The heroin is Lin Qiaozhi, a famous medical scientist, made a great contribution to our country’s medical care. Most importantly, her life experience can inspire our students whether in studying or the development of career. she had moral dilemmas and life choices, which are similar to the students who will step into society. Besides, Lin has quite good virtues like kindness, self-improvement, insistence, job-loving , generosity and responsibility, which is worth being learned.Concretely, this article is a biography about Lin Qiaozhi. The article tells her whole life according the timeline, among which the life choices is emphasized. For example, whether married or chased her dream, returned home or stayed abroad, family or public, her choices all reflected her faith, spirit, responsibility and devotion.1. Fast reading to get the detailed information about Lin Qiaozhi; careful reading to do the deductive information.2. Learn the reading skills--deductive judgement according the context.3. Study the structure features and language features. 4. Communicate about Lin’s life choices and reflect their own life choices.1. Learn the reading skills--deductive judgement according the context.2. Study the structure features and language features.3. Communicate about Lin’s life choices and reflect their own life choices.Step 1 Lead in---Small talkWhat are some important life choices?Importance choices: university study, jobs and marriage partners. Because they can determine our future.
1. 这个寓言是一个关于一位国王古寓言。 The fable is an old fable about a king.2.作者用这个故事让读者对于社区的问题负有个人责任的必要印象深刻。The author used the story to impress upon readers with the need to take personal responsibility for problems in the community.3. 这个故事十分成功的实现了它的目的。The story was quite successful in achieving its purpose.Step 7 WritingPlease write a review of the story according the outline above.The fable is an old fable about a king who thought his people are lazy, so he put a large stone in the middle of the road and hides and waited to see if anyone will try to move it.The author used this story to impress upon readers with the need to take personal responsibility for problems in the community. The story was quite successful in achieving its purpose, and I liked it because it had a clear moral.However, while the moral of the story is clear, the actions of the king seemed pointless to me, because none of the characters in the story learnt anything. For this reason, I think there are better stories that can be used to impress upon people with the need for personal responsibility.Step 8 Pair workExchange drafts with a partner. Use this checklist to help your partner revise his/her draft.1. Does the writer give a short description of the story ?2. Does the description include the most important details of the story ?3. Does the writer give his or her opinion about the character or their actions ?4. Is the review well-organised ? 5. Does the writer use the -ing form as the adverbial correctly in the writing ?6. Are there any grammar, spelling, or punctuation errors ?Step 9 HomeworkPut up your revised draft in the classroom or read it to your class.
The topic of this part is “Describe a place with distinctive cultural identity”.This section focuses on Chinese culture by introducing Chinatown, whose purpose is to show the relationship between the Chinese culture and American culture. The Chinese culture in Chinatown is an important part of American culture. Chinatown is an important window of spreading Chinese culture and the spirit homeland of oversea Chinese, where foreigners can experience Chinese culture by themselves.Concretely, the title is “Welcome to Chinatown!”, from which we can know that the article aims at introducing Chinatown. The author used the “Introduction--Body Paragraph--Conclusion” to describe the people, language, architecture, business, famous food and drinks and people’s activities, which can be a centre for Chinese culture and shows its unique charm.1. Read quickly to get main idea; read carefully to get the detailed information.2. Learn the characteristics of writing and language.3. Learn to introduce your own town according to the text.4. Learn to correct others’ writing.1. Learn the characteristics of writing and language.2. Learn to introduce your own town according to the text.Step 1 Lead in ---Small talkIn the reading part, we mentioned the Chinatown of San Francisco. How much do you know about Chinatown of San Francisco ?Chinatown is a main living place for Chinese immigrants, where you can see many Chinese-style buildings, costumes, operas, restaurants, music and even hear Chinese.Step 2 Before reading ---Predict the contentWhat is the writer’s purpose of writing this text ? How do you know ?From the title(Welcome to Chinatown) and some key words from the text(tourist, visit, visitors, experience), we can know the purpose of the text is to introduce Chinatown and show the relationship between Chinese culture and American culture.
Discuss these questions in groups.Q1: Have you ever been to a place that has a diverse culture ? What do you think about the culture diversity ?One culturally diverse place that I have been to is Harbin, the capital city of Heilongjiang Province. I went there last year with my family to see the Ice and Snow Festival, and I was amazed at how the culture as different to most other Chinese cities. There is a big Russian influence there, with beautiful Russian architecture and lots of interesting restaurants. I learnt that Harbin is called “the Oriental Moscow” and that many Russians settled there to help build the railway over 100 years ago.Q2: What are the benefits and challenges of cultural diversity ?The benefits: People are able to experience a wide variety of cultures, making their lives more interesting, and it can deepen the feelings for our national culture, it is also helpful for us to learn about other outstanding culture, which helps improve the ability to respect others. The challenges: People may have trouble communicating or understanding each other, and it may lead to disappearance of some civilizations and even make some people think “The western moon is rounder than his own.”Step 7 Post reading---RetellComplete the passage according to the text.Today, I arrived back in San Francisco, and it feels good (1) _____(be) back in the city again. The city succeeded in (2)_________ (rebuild) itself after the earthquake that (3)________ (occur) in 1906, and I stayed in the Mission District, enjoying some delicious noodles mixed with cultures. In the afternoon, I headed to a local museum (4)____ showed the historical changes in California. During the gold rush, many Chinese arrived, and some opened up shops and restaurants in Chinatown to earn a (5)_____ (live). Many others worked on (6)______ (farm), joined the gold rush, or went to build the railway that connected California to the east. The museum showed us (7)____ America was built by immigrants from (8)________ (difference) countries and cultures. In the evening, I went to Chinatown, and ate in a Cantonese restaurant that served food on (9)________(beauty) china plates. Tomorrow evening, I’m going to (10)__ jazz bar in the Richmond District. 答案:1. to be 2. rebuilding 3. occurred 4. that 5.living6. farms 7.how 8. different 9. beautiful 10. a
Listening and Speaking introduces the topic of “talking about how to become an astronaut”. This period is aimed to inform students some details about the requirements of being an astronaut. Students can be motivated and inspired by the astronauts. Teachers ought to encourage students to learn from them and let them aim high and dream big.Listening and Talking introduces the theme of "talk about life in space". This part also informs students more details about life in space and can inspire students to be curious about this job. 1. Guide students to listen for numbers concerning dates, years and ages etc2. Cultivate students' ability to talk about how to become an astronaut and life in space ; 3. Instruct students to use functional sentences of the dialogue such as “ first of all, I am not sure, so what might be .. I guess.. I wonder…I am curious…)appropriately.1. Guide students to understand the content of listening texts in terms of the whole and key details; 2. Cultivate students' ability to guess the meaning of words in listening; discuss with their peers how to become a qualified astronaut and describe the life in space.Part 1: Listening and SpeakingStep 1: Lead inPredictionThe teacher can ask students to predict what the listening text is about by looking at the pictures.About how to become an astronaut./the requirements of an astronautStep 2: Then, play the radio which is about an interview a. And after finishing listening for the first time, the students need to solve the following tasks.
The theme of this unit focuses on “space exploration.” Students will learn about the training and experience needed to become an astronaut. The text is mainly about the development of space exploration. On the one hand, the text helps students to have a good understanding about the great feats humans have achieved, on the other hand, they will further understand the contributions that we Chinese have achieved, and feel confident and proud about our homeland and strengthen their love for our country. The teacher should instruct students to aim high and study harder to make great progress in the space career if possible.1. Read about the development and value of space exploration.2. Explore the mysteries of the universe and the achievements in space exploration.3. Skillfully use the vocabulary of this text to cultivate self-study ability 4. Develop cooperative learning ability through discussion.1. Enable the Ss to talk about the development and value of space exploration.2. Guide the Ss to summarize the main idea of each paragraph as well as the main idea of the text.3. Help Ss comprehend the main reasons for space exploration. Multi-media, textbook, notebooks.Step 1: Warming up and predictionLook at the title and the pictures of the text and predict what the text will be about?2. What are the main reasons for space exploration?
另一方面,其余的人反对这个计划,因为它可能会导致一些不好的影响。7.I hold the belief that space exploration not only enable us to understand how the universe began but also help us survived well into the future.我坚信探索太空不仅能够使我们了解宇宙的起源而且能够帮助我们更好地走进未来。8.I think we should spend more time and money exploring space so as to provide new and better solutions to people's shortterm and longterm problems.为了给人类的短期和长期问题提供更新和更好的解决方法,我认为我们应该花更多的时间和金钱来探索太空。9.From my point of view,it is wrong of young people to depend on their telephones too much,which may do harm to both their physical and mental health.在我看来,年轻人过度依赖手机是不对的,因为它们可能会对他们的身心健康都有害。最近你班同学就“人类是否应该进行宇宙探索”这个问题进行了激烈的讨论。有人认为,探索宇宙不仅让人类更好地了解宇宙的发展,还可以用来指导农业生产,以及把一些探索太空的高新技术用于现实生活;也有一些人认为探索太空花掉了大量的人力物力;影响了人们的生活水平。请你根据以下情况写一篇报告并发表自己的观点。注意:1.写作内容应包括以上全部要点,可适当发挥,使上下文连贯;
PPT全称是PowerPoint,LFPPT为你提供免费PPT模板下载资源。让你10秒轻松搞定幻灯片制作,打造⾼颜值的丰富演示文稿素材模版合集。