(3)师生讨论,提升思维深度。教师引领学生将讨论由农业生态破坏、土地利用不合理等表象问题逐步深入到农业结构不合理、农业技术落后等深层问题,提升了学生思维的深度。(4)角色体验,突破难点落实重点。在农民与保护区工作人员的角色体验活动中,学生们尝试换位思考,在冲突与交锋中,在教师的引领下,重新认识环境保护与区域经济发展的关系,在情感体验中加深对可持续发展内涵的理解,小冲突凸显大矛盾是本课设计的创新之处。2.注重对地理问题的探究,突出地理学科本质。地理学科具有综合性、区域性特征,区域差异及人地和谐发展观是我们在教学中应该把握的基本特征,也是我们应当把握的地理学科的本质特征,因此在本节课的设计中我注重抓住地理事物的空间特征、综合性特征,以突出地理学科的本质。
由于这部分知识已要求学生在课前收集相关资料探讨分析,,现在提供机会让他们进行交流,充分发表各自的见解。所以,学生对这个知识掌握起来并不难。所以,我对这部分内容不做太多的讲解,只要做进一步的梳理,加深学生的理解即可。 第三是小结环节 在学生对西气东输工程的原因掌握之后进入的是小结环节,这里我进一步提出问题:在西气东输工程段的建设中有没有什么难关? 通过西气东输的难度了解,间接的表现我国的科技的发展,增加学生的爱国情,同时也说明西气东输的建成也有技术这一原因。从而也完成了本课时的小结。 第四环节是作业布置 在这里要求学生课后预习本课剩下的内容:思考西气东输对区域发展的影响以及为何要实施资源的跨区域调配。通过这样的问题一方面为下节课学习奠定基础,另一方面体现本课学习从“个”到“类”从特殊到一般的过程。
问题导学类比用方程研究椭圆双曲线几何性质的过程与方法,y2 = 2px (p>0)你认为应研究抛物线的哪些几何性质,如何研究这些性质?1. 范围抛物线 y2 = 2px (p>0) 在 y 轴的右侧,开口向右,这条抛物线上的任意一点M 的坐标 (x, y) 的横坐标满足不等式 x ≥ 0;当x 的值增大时,|y| 也增大,这说明抛物线向右上方和右下方无限延伸.抛物线是无界曲线.2. 对称性观察图象,不难发现,抛物线 y2 = 2px (p>0)关于 x 轴对称,我们把抛物线的对称轴叫做抛物线的轴.抛物线只有一条对称轴. 3. 顶点抛物线和它轴的交点叫做抛物线的顶点.抛物线的顶点坐标是坐标原点 (0, 0) .4. 离心率抛物线上的点M 到焦点的距离和它到准线的距离的比,叫做抛物线的离心率. 用 e 表示,e = 1.探究如果抛物线的标准方程是〖 y〗^2=-2px(p>0), ②〖 x〗^2=2py(p>0), ③〖 x〗^2=-2py(p>0), ④
二、直线与抛物线的位置关系设直线l:y=kx+m,抛物线:y2=2px(p>0),将直线方程与抛物线方程联立整理成关于x的方程k2x2+2(km-p)x+m2=0.(1)若k≠0,当Δ>0时,直线与抛物线相交,有两个交点;当Δ=0时,直线与抛物线相切,有一个切点;当Δ<0时,直线与抛物线相离,没有公共点.(2)若k=0,直线与抛物线有一个交点,此时直线平行于抛物线的对称轴或与对称轴重合.因此直线与抛物线有一个公共点是直线与抛物线相切的必要不充分条件.二、典例解析例5.过抛物线焦点F的直线交抛物线于A、B两点,通过点A和抛物线顶点的直线交抛物线的准线于点D,求证:直线DB平行于抛物线的对称轴.【分析】设抛物线的标准方程为:y2=2px(p>0).设A(x1,y1),B(x2,y2).直线OA的方程为: = = ,可得yD= .设直线AB的方程为:my=x﹣ ,与抛物线的方程联立化为y2﹣2pm﹣p2=0,
通过列表对比法、归纳法、、多媒体辅助法等教学方法,突破理论性强、不宜理解的“3S”原理与区别的知识难点。学生更是学会运用图表方法、高效记忆法、合作学习法等方法学习地理知识,增加学习能力。[幻灯片] “3S技术”的应用:地理信息技术的应用十分广泛,从实际身旁的社会生产生活,到地理学的区域地理环境研究。学生的年龄和认知范围决定,此部分的案例教学的运用,前者容易接触到、简单直观、易区分掌握“3S”技术特点和具体应用。而后者涉及地理学科的综合性和区域性的特点,难度较大。针对学情特点,我多以前者案例入手学习,以后者案例加以补充。案例:遥感:(1)视频 专家解说卫星遥感受灾影象(2)教材 图1.6 1998年8月28日洞庭湖及荆江地区卫星遥感图像(3)视频 2008年5月13日“北京一号”卫星提供汶川的灾区遥感图像(4)教材 阅读 遥感在农业方面的应用
1、《战后资本主义世界经济体系的形成》是人教版高中历史必修Ⅱ第八单元第22课,学时为1课时。《历史必修Ⅱ》一书用古今贯通、中外关联的八个专题来着重反映人类社会经济和社会生活领域发展进程中的重要史实。从第一单元勾勒“古代中国经济的基本结构与特点”再到第八单元“世界经济的全球化趋势”,以历史唯物主义观点清晰阐明经济全球化是世界生产力发展的要求和结果,是不以人的意志为转移的历史必然趋势。第八单元的标题是《世界经济的全球化趋势》,作为最后一单元,从内容上讲,有强烈的时代感和现实意义,是全书内容的总结与升华展望。提起“全球化”这个十年前才首次出现在美国《商业周刊》的新名词,如今却是地球人都知道了。然而究竟什么是全球化?作为一历史现象,全球化有其自身内部严密完整的体系,其中核心之一便是制度、规则的全球化,而这正是本课内容的着力点。
(2)l的倾斜角为90°,即l平行于y轴,所以m+1=2m,得m=1.延伸探究1 本例条件不变,试求直线l的倾斜角为锐角时实数m的取值范围.解:由题意知(m"-" 1"-" 1)/(m+1"-" 2m)>0,解得1<m<2.延伸探究2 若将本例中的“N(2m,1)”改为“N(3m,2m)”,其他条件不变,结果如何?解:(1)由题意知(m"-" 1"-" 2m)/(m+1"-" 3m)=1,解得m=2.(2)由题意知m+1=3m,解得m=1/2.直线斜率的计算方法(1)判断两点的横坐标是否相等,若相等,则直线的斜率不存在.(2)若两点的横坐标不相等,则可以用斜率公式k=(y_2 "-" y_1)/(x_2 "-" x_1 )(其中x1≠x2)进行计算.金题典例 光线从点A(2,1)射到y轴上的点Q,经y轴反射后过点B(4,3),试求点Q的坐标及入射光线的斜率.解:(方法1)设Q(0,y),则由题意得kQA=-kQB.∵kQA=(1"-" y)/2,kQB=(3"-" y)/4,∴(1"-" y)/2=-(3"-" y)/4.解得y=5/3,即点Q的坐标为 0,5/3 ,∴k入=kQA=(1"-" y)/2=-1/3.(方法2)设Q(0,y),如图,点B(4,3)关于y轴的对称点为B'(-4,3), kAB'=(1"-" 3)/(2+4)=-1/3,由题意得,A、Q、B'三点共线.从而入射光线的斜率为kAQ=kAB'=-1/3.所以,有(1"-" y)/2=(1"-" 3)/(2+4),解得y=5/3,点Q的坐标为(0,5/3).
反思感悟用基底表示空间向量的解题策略1.空间中,任一向量都可以用一个基底表示,且只要基底确定,则表示形式是唯一的.2.用基底表示空间向量时,一般要结合图形,运用向量加法、减法的平行四边形法则、三角形法则,以及数乘向量的运算法则,逐步向基向量过渡,直至全部用基向量表示.3.在空间几何体中选择基底时,通常选取公共起点最集中的向量或关系最明确的向量作为基底,例如,在正方体、长方体、平行六面体、四面体中,一般选用从同一顶点出发的三条棱所对应的向量作为基底.例2.在棱长为2的正方体ABCD-A1B1C1D1中,E,F分别是DD1,BD的中点,点G在棱CD上,且CG=1/3 CD(1)证明:EF⊥B1C;(2)求EF与C1G所成角的余弦值.思路分析选择一个空间基底,将(EF) ?,(B_1 C) ?,(C_1 G) ?用基向量表示.(1)证明(EF) ?·(B_1 C) ?=0即可;(2)求(EF) ?与(C_1 G) ?夹角的余弦值即可.(1)证明:设(DA) ?=i,(DC) ?=j,(DD_1 ) ?=k,则{i,j,k}构成空间的一个正交基底.
(六)说教学策略1.专题性海量的媒介信息必须加以选择或者整合,以项目为依据,进行信息筛选,形成专题性阅读与交流;培养学生对文本信息“化零为整”的能力,提升跨媒介阅读与交流学习的充实感。2.情境化情境教学应指向学生的应用,建构富有符合时代气息的内容,与生活经验更加贴合,对学生的语言建构与运用有所提升,在情境中能够有效地进行交流。3.任务化以任务为导向的序列化学习,可以为学生构建学习路线图、学习框架等具体任务引导;或以跨媒介的认识与应用为任务的设置引导;甚至以阅读和交流作为序列化安排的实践引导。4.整合性跨媒介阅读与交流是结合线上线下的资源,形成新的“超媒介”,也能实现对信息进行“深加工”,多种媒介的信息整合只为一个核心教学内容服务。5.互文性语言文字是语文之生命,我们是立足于语言文字的探讨,音乐、图像、视频等文本与传统语言文字文本形成互文,触发学生对学习内容立体化和具体化的感悟,提升学生的审美能力。
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
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.
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.
1. 表示时间。Hearing these stories, I’m skeptical about the place. = When I heard these stories. . . 2. 表示原因。Not knowing his address, I can’t send this book to him. = Because/Since/As I don’t know his address. . . 3. 表示结果。His father died, leaving him a lot of money. =. . . and left him a lot of money4. 表示条件。Going straight down the road, you will find the department store. = If you go straight down the road. . . 5. 表示让步。Being tired, they went on working. =Although they were tired. . . 6. 表示行为方式、伴随情况或补充说明。He lay on the grass, staring at the sky for a long time. =. . . and stared at the sky for a long time注意:非谓语动词作状语时, 如所提供的动词不能和句子中的主语保持一致, 动词-ing形式必须有自己的逻辑主语, 通常由名词或代词来担任, 这就是独立主格结构。The last bus having gone, we had to walk home. (having gone的逻辑主语是the last bus, 而不是we)Weather permitting, the football match will be played on Friday. (permitting的逻辑主语是time, 而不是the football match)Step 7 Practice1. ________(study) hard, you are sure to get first prize. 2. People use plastic in their daily life, _______(leave) large amounts of waste. 3. ________(work) hard at your lessons, you are to succeed. 4. The old man, ____________(work) abroad for twenty years, is on the way back to his motherland. 5. ______________(finish) his homework, he was playing on the playground. Answers: 1. Studying 2. leaving 3. Working 4.having worked 5. Having finishedStep 8 HomeworkFinish the homework on Page 22.
Example:One day, a poor boy who was trying to pay his way through school by sending newspapers door to door found that he only had one dime(一角)left. He was so hungry that he decided to beg for a meal at the next house.However, he lost his nerve when a lovely young woman opened the door. Instead of a meal he asked for a drink of water. She thought he looked hungry so she brought him a large glass of milk. He drank it slowly, and then asked, “How much do I owe you?” “You don’t owe me anything,” she replied, “Mother has taught me never to accept pay for a kindness.” “Then I thank you from the bottom of my heart.” With these words, Howard Kelly left that house.Years later the woman became badly ill and was finally sent to the hospital in a big city. Dr. Howard Kelly, now famous, was called in. When he heard the name of the town she came from, a strange light filled his eyes. Dressed in his doctor’s clothes, Dr. Kelly went into her room and recognized her at once. From that day on, he gave special attention to her, and decided to do his best to save her life.At last the woman was saved. Dr. Kelly asked the business office to pass the final bill to him. He looked at it and then wrote something on the side. The bill was sent to the woman’s room. She was afraid to open it because she was sure that it would take the rest of her life to pay for it off. Finally she looked, and the note on the side of the bill caught her attention. She read these words: “Paid in full with a glass of milk, Dr. Howard Kelly.” Tear of joy flooded her eyes.
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. In Picture 1 and Picture 2, where do you think they are from? How do you know?From their wearings, we can know they are from ethnic minority of China--- Miao and Dong.Picture 1, they are playing their traditional instrument lusheng in their traditional costumes.Picture 2. the girls are Miao because they wear their traditional costumes and silver accessory.2. In Picture 3, can you find which village it is? What time is it in the picture?It is Dong village. It is at night. Step 2 While-listeningJustin met a new friend while traveling in Guizhou. Listen to their conversation and complete the summaries below.Part 1Justin and Wu Yue watched some Miao people play the lusheng. The instrument has a history of over 3,000 years and it is even mentioned in the oldest collection of Chinese poetry. Then they watched the lusheng dance. Justin wanted to buy some hand-made silver/traditional accessories as souvenirs. He was told that the price will depend on the percentage of silver. Part 2They will go to a pretty Dong minority village called Zhaoxing. they will see the drum towers and the wind and rain bridges. They may also see a performance of the Grand Song of the Dong people.Step 3 Post-listening---TalkingWork in groups. Imagine Justin is telling some friends about his trip to Guizhou. One of you is Justin and the rest of you are his friends. Ask Justin questions about his trip and experience. The following expressions may help you.
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
? Could you offer me some kind of work here?? I don’t want your charity, I just want an honest job.? Careless: I landed in Britain by accident.Step 7:Consolidation.? Find Henry? Roderick and Oliver were I .making a bet when they saw Henry, a poor young man. ? Know Henry? About a month ago, Henry was sailing and later he found himself carried out to sea by a strong wind. Fortunately, he 2.was spotted by a ship. And it was the ship that brought him to 3.England? Offer money to Henry ? Oliver and Roderick gave Henry a letter and told him that there was money in it. They 4.persuaded him to accept it, and made him 5.promise that it wouldn't be opened until 2 o'clock.Step 8:Language pointsa large amount of: a large quantity of; a great deal ofe.g. They bought a large amount of furniture before they moved their new house.make a bet: make an arrangement to risk money, etc. on an event of which the result is doubtful.e.g. We made a bet on the result of the match.permit sb to do something: allow somebody to do somethinge.g. My mother doesn’t permit me to ride in the street after it rained.by accident: as a result of chancee.g. I only found it by accident.stare at: look at somebody or something with the eyes wide open in a fixed gaze( in astonishment, wonder, fear, etc)to be honest: to tell you the truth; to be franke.g. To be honest, I don’t think we have a chance of winning.Step7 Homework:What do you think will happen to Henry? Will the bank-note help him or get him into trouble?
Everybody wants to get wealth.In today’s material world,making money or becoming wealthy symbolizes a person’s success and capability. Many people just make every effort, pay any price to attain greater wealth. With money,they can buy nice, large apartments in nice neighborhood. With money they can own luxurious cars. Wealth seems to bring all happiness in life.But is wealth the only road to happiness? Not really. There are many things in the world, which are beyond the means of money, such as friendship, love, health and knowledge. People are so preoccupied with struggling for money that they have no time or would not take the time to form or maintain friendship. What happiness can they feel living as lonely miserable creatures without love or friends in the world even if they accumulate tremendous wealth?In my opinion, people can’t do anything without money, but money is not everything. What money will bring you depends on your personal belief and goal in life. If you are kind enough to help others, especially the poor, money is a good thing to you. With it, you can do much more for the benefit of people and your country, and it will add to your own happiness. If you want money just for your own needs, you’ll never be satisfied or happy. In a word,you should have money spent for more people. Only then can money be the source of your happiness.Step 8 Homework4 students in a group, one acts Roderick, one Oliver, one servant and the fourth one acts Henry Adams, then listen to the tape, pay more attention to the difference between American English and British English in pronunciation, stress, tone.
导语在必修第一册中,我们研究了函数的单调性,并利用函数单调性等知识,定性的研究了一次函数、指数函数、对数函数增长速度的差异,知道“对数增长” 是越来越慢的,“指数爆炸” 比“直线上升” 快得多,进一步的能否精确定量的刻画变化速度的快慢呢,下面我们就来研究这个问题。新知探究问题1 高台跳水运动员的速度高台跳水运动中,运动员在运动过程中的重心相对于水面的高度h(单位:m)与起跳后的时间t(单位:s)存在函数关系h(t)=-4.9t2+4.8t+11.如何描述用运动员从起跳到入水的过程中运动的快慢程度呢?直觉告诉我们,运动员从起跳到入水的过程中,在上升阶段运动的越来越慢,在下降阶段运动的越来越快,我们可以把整个运动时间段分成许多小段,用运动员在每段时间内的平均速度v ?近似的描述它的运动状态。
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