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人教版高中地理必修2第一章第三節(jié)人口的合理容量說課稿
【教學目標】知識與技能：理解環(huán)境承載力與環(huán)境人口容量的含義、兩者的關系以及環(huán)境人口容量的影響因素；理解人口合理容量的含義，影響因素并掌握保持人口合理容量的做法；結合中國國情提出適合中國保持合理人口容量的措施過程與方法：通過問題探究及案例分析理解環(huán)境承載力與環(huán)境人口容量的關系及影響因素；通過問題探討掌握保持人口合理容量的措施。情感態(tài)度與價值觀：樹立并強化學生的可持續(xù)發(fā)展觀念，科學發(fā)展觀。激發(fā)學生愛國情感更多地關注國家國情，樹立主人翁意識保護地球強大祖國?！窘虒W重點】環(huán)境人口容量的內涵以及影響因素人口合理容量的影響因素以及措施【教學難點】環(huán)境人口容量的內涵以及影響因素人口合理容量的影響因素以及措施二、說教法【教學方法】案例分析、問題探究、歸納總結
人教版高中歷史必修1新中國的民主政治建設說課稿2篇
（一）教材的地位新中國的成立是20世紀的一件大事。它結束了幾千年封建專制統(tǒng)治的歷史，開啟了中華民族發(fā)展的新紀元。本課側重這一時期一個非常顯著的特征，即制度的更新，它本身具有知識的延續(xù)性和鋪墊性。新中國的成立促進了社會經濟的發(fā)展，也為祖國的統(tǒng)一奠定了重要基礎。（二）教學目標依據(jù)新課程以人為本，促進學生全面發(fā)展的要求，同時,針對高一年級學生具備一定基礎知識但掌握不牢固，對歷史興趣濃厚但又自制能力差的特點，我對本課的三維目標設定如下：見多媒體。（三）教學重點的確定及處理本課的主題是新中國的民主政治建設，這個問題的掌握對以后學習中國民主政治建設的進程有很大幫助，并且學生能力的提高也有賴于對它的認識，所以確定“人民代表大會制度的創(chuàng)立”是教學重點。
人教版高中生物必修3第四章第三節(jié)《群落的結構》說課稿
建構群落特征3群落有一定的空間結構，包括垂直結構和水平結構。思維拓展從結構與功能相統(tǒng)一的角度思考群落內的分層結構的意義。6.4運用群落核心知識概念解決未知群落問題學生已掌握了同一時間內聚集在一定區(qū)域中各種生物種群的集合是生物群落，所有群落都有一定的物種組成、種間關系、空間結構，不同群落主要表現(xiàn)在其具體特征上的差異。在此基礎上，為學生提供新的問題情境，利用多媒體課件，展示不同生態(tài)環(huán)境下不同生物群落問題，讓學生運用已建構的群落概念，通過分析、演繹和具體化等辯證思維的過程解決未知的群落問題，課件展示熱帶雨林、溫帶草原、海洋、湖泊等生物群落。學生運用概念說明不同的群落的物種豐富度差異，列舉不同群落的種間關系，分析不同群落的垂直結構和水平結構，研究造成不同群落重要特征差異的原因。評價人類的活動對群落的結構的影響。
人教版高中生物必修3第五章第三節(jié)《生態(tài)系統(tǒng)的物質循環(huán)》說課稿
步驟四：展示點評、質疑探究展示小組展示討論論成果，要求每組B、C層次學生進行展示。展示結束后由點評同學對展示結果進行點評，要求先點評對錯；再點評思路方法和應注意的問題。既要有結論，又要有分析，力爭有相關的總結和拓展。下面的同學注意傾聽、思考，關鍵內容做好筆記，有補充或不明白的地方及時、大膽提出，力爭全部過關，解決疑難點。根據(jù)學生點評結果，教師適當點評拓展。步驟五：拓展提升、總結升華簡單扼要的課堂小結，系統(tǒng)回顧知識，強化學生對于生態(tài)系統(tǒng)物質循環(huán)的認識。環(huán)節(jié)三：課后檢測布置訓練內容，鞏固知識。五、課后反思：本堂課采用我校163高效課堂模式，通過小組合作探究、展示自我、互相點評的方式完成整堂課的教學內容，充分突出了新課標中以學生為主體的指導思想。教學過程中，依據(jù)學生的個性差異，提出不同要求，布置不同任務，讓不同層次的學生都能參與其中，調動全體學生的積極性，促進全體學生的發(fā)展。
人教版高中地理必修1第二章第三節(jié)常見的天氣系統(tǒng)說課稿
一、說教材（一）教材的地位與作用本節(jié)內容是本單元知識結構中重要的一環(huán)，具有承上啟下的作用。由于各種天氣現(xiàn)象的產生與大氣的熱力狀況、大氣的運動有密切的聯(lián)系，所以，本課是在綜合前兩節(jié)內容的基礎上，闡述常見的天氣現(xiàn)象的成因。在實際生活中，天氣系統(tǒng)與人們的生產、生活密切相關。本課所講的內容對于學生了解天氣變化的最基本因素，普及天氣預報知識具有積極的意義。（二）教學目標(1)知識與技能目標：⑴從圖片和簡易圖中，知道氣團（冷氣團、暖氣團）的概念；鋒的概念與分類；低壓（氣旋）、高壓（反氣旋）、高壓脊、低壓槽的概念。 ⑵從氣溫、氣壓、濕度、降水、風等幾方面分析各種天氣系統(tǒng)的形成及其氣流特點，并綜合出各種天氣系統(tǒng)控制下的天氣狀況。⑶知道低壓槽和高壓脊概念及在圖上的表示方法。(2)過程與方法目標：⑴讓學生能閱讀和簡單分析天氣圖，解釋天氣變化現(xiàn)象；⑵用案例說明氣象災害發(fā)生的原因和危害；
人教版高中地理必修1第一章第三節(jié)地球的運動說課稿
（一）教材的地位與作用“地球的運動”是地理環(huán)境的形成以及地理環(huán)境各要素運動變化的基礎，因而也是高中階段地理學習的基礎。“地球公轉與季節(jié)”是在介紹完“地球運動的一般特點”和“地球自轉與時差”之后進行的；（二）教學目標(1)知識與技能目標：1.掌握全球各緯度晝夜長短和正午太陽高度變化的規(guī)律；2.懂得運用地球運動的有關知識解釋生活現(xiàn)象和分析實際問題。(2)過程與方法目標：1.通過前后關聯(lián)知識點層層遞進的學習，讓學生學會運用相關圖表來分析地理問題，并能理論和實際相結合綜合分析和解決問題。（加強對圖表分析能力的培養(yǎng)，是地理學科的突出特點。）(3)情感、態(tài)度與價值觀目標：1.使學生初步了解地球上許多地理現(xiàn)象都同地球的運動有關，從而對學生進行唯物主義教育，培養(yǎng)學生熱愛科學和勇于探索的精神。
人教版高中歷史必修1從漢至元政治制度的演變說課稿2篇
二、君主專制的演進（即中央政治制度的演變）通過地方政治制度演變的學習，掌握方法以后，以學生歸納整理基本線索為主，教師適當點撥，注意糾錯。1． 漢承秦制，又有所變化。教師點撥強調繼承與發(fā)展兩個方面。創(chuàng)設情景：同學們看了電視連續(xù)劇《漢武大帝》后，知道漢武帝劉徹在繼位之后，就急于對西漢王朝的政治制度進行改革。那么，西漢初期中央政治制度的基本框架是怎樣的呢？漢武帝為什么要對它進行改革呢？改革后的西漢中央集權制度又是怎樣的呢？請大家議一議，想一想。主干知識：西漢初期的中央政治制度的最大特點是“漢承秦制”。具體表現(xiàn)在兩個方面：一是繼續(xù)實行皇帝制度，維護皇權，這一做法也為后來各王朝所沿用；二是在中央設立三公，分別掌管行政、監(jiān)察和軍事。到漢武帝時，“中朝”成為西漢重要的中央決策機構，尚書令的權力日益重要，以丞相為首的三公九卿的權力被削弱，演化為執(zhí)行機構。到了東漢光武帝時，進一步剝奪三公權限，擴大尚書的權力。
人教版高中歷史必修1資本主義政治制度在歐洲大陸的擴展說課稿
1789年法國大革命后，共和派與君主派之間進行了長期反復的斗爭，直到1875年法蘭西第三共和國憲法通過才最終確立了共和政體，它為法國資本主義的進一步發(fā)展奠定了基礎。專制色彩濃厚的普魯士通過王朝戰(zhàn)爭這種自上而下的形式，完成了德國的統(tǒng)一。1871年德意志帝國憲法頒布，德國君主立憲政體確立，保留了濃厚的專制殘余和軍國主義傳統(tǒng)。但資產階級代議制的建立使德國的資本主義工業(yè)迅速發(fā)展起來，19世紀末躋身到世界強國行列。資本主義政治制度擴展到了歐洲大陸，隨著這兩個國家資本主義政治制度的確立，近代西方主要資本主義政治制度得以最終確立。四、板書一、法國共和政體確立的艱難歷程1、艱難 （1）表現(xiàn) （2）原因2、確立標志：法蘭西第三共和國憲法
人教版高中歷史必修1夏、商、西周的政治制度說課稿3篇
二、教學目標：（一）知識與能力：學生了解夏商周期的政治制度的內容和特點，對不同的政治制度有一個較為全面的認識。在此基礎上，學生根據(jù)所學的知識，歸納和評價從夏到周政治發(fā)展的特點以及內在規(guī)律。（二）過程與方法：在學習的過程中，采用小組合作討論的形式，讓學生學會與他人合作與溝通，提高自主探究的技能。（三）情感態(tài)度與價值觀：政治制度的不斷更新是古人制度創(chuàng)新的結果，而這種制度的不斷更新也推動文明的發(fā)展。這是古代先民的智慧結晶，學生要引以為豪。而通過本課的學習，可以增強學生們的民族自豪感。三、說教科書：本課作為高中歷史教材的開篇，是認識整個古代政治文明史的起點，具有統(tǒng)領和示范作用。本課總共有三個子目,主要講述了夏商周的政治制度。主要介紹了夏朝公共權力的出現(xiàn)，分封制的內容、分封的對象、 “以嫡長子繼承制為核心的宗法制度”介紹了宗法制的來源、內容，以及禮樂制度的大致內容。
人教部編版道德與法制五年級下冊新版奪取抗日戰(zhàn)爭和人民解放戰(zhàn)爭的勝利說課稿第二課時
1.師要注意區(qū)別教學內容是否適合進行小組合作探究。這種學習是否每節(jié)課都需要。學生的小組學習是否在走過場，或者說流于形式。教師要注意營造自由自在的學習氛圍，控制討論的局面，如討論中是否有人進行人身攻擊，是否有人壟斷發(fā)言權而有的人卻一言不發(fā)，是否有人竊竊私語，教師要在巡視及參與中“察言觀色”，及時調控。2.教師要充分注意精心設計的問題。教師的教學設計是否合適，是做秀還是教學的需要。這不僅需要教師的認同，還需要課程的認同，學生的認同。因此，對于適合采用小組合作探究方式的教學內容，我們一定要根據(jù)課程標準的三維目標學生現(xiàn)有的認知程度和興趣以及本課要解決的問題和教學任務來精心設計問題。3.要注重小組合作探究的組織,進行適當有效的指導。教師要轉換自己的角色，從傳授者變成指導者、參與者、監(jiān)控者和幫助者，并切實注意自身行為的方法和效果，及時進行調整。
人教部編版道德與法制五年級下冊新版屹立在世界的東方說課稿第一課時
討論交流：正是靠著這種民族精神，我國建成了一個個大油田。到1965年，中國的石油基本實現(xiàn)自給。5、補充資料1964年10月16日和1967年6月17日，中國西北羅布泊大漠中，升起了蘑菇狀的煙云。我國相繼成功爆炸了第一顆原子彈和第一顆氫彈，成為繼美國、蘇聯(lián)、英國之后第四個同時擁有原子彈和核彈的國家。中國從此擁有了保家衛(wèi)國、捍衛(wèi)和平的核力量。交流鄧稼先故事1950年8月，鄧稼先在美國獲得博士學位九天后，便謝絕了恩師和同校好友的挽留，毅然決定回國。同年10月，鄧稼先來到中國科學院近代物理研究所任研究員。在北京外事部門的招待會上，有人問他帶了什么回來。他說：“帶了幾雙眼下中國還不能生產的尼龍襪子送給父親，還帶了一腦袋關于原子核的知識?！贝撕蟮陌四觊g，他進行了中國原子核理論的研究。
人教版高中地理必修3地理信息技術在區(qū)域地理環(huán)境研究中的應用教案
1．從監(jiān)測的范圍、速度，人力和財力的投入等方面看，遙感具有哪些特點?點撥：范圍更廣、速度更快、需要人力更少 、財力投入少。2．有人說：遙感是人的視力的延伸。你同意這種看法嗎?點撥：同意?？梢詮倪b感的定義分析。從某種意義上說，人們“看”的過程就是在遙感，眼睛相當于傳感器。課堂小結：遙感技術是國土整治和區(qū)域發(fā)展研究中應用較廣的技術 手段之一，我國在這個領域已經走在了世界的前列。我國的大部分土地已經獲得了大比例尺的航空影像資料，成功發(fā)射了回收式國土資源衛(wèi)星，自行研制發(fā)射了“風云”衛(wèi)星。遙感技術為我國自然資源開發(fā)與利用提供 了大量的有用的資料，在我國農業(yè)估產、災害監(jiān)測 、礦產勘察、土地利用、環(huán)境管理與城鄉(xiāng)規(guī)劃中起到了非常重要的作用。板書設計§1.2地理信息技術在區(qū)域地理環(huán)境研究中的應用
人教版高中歷史必修1八國聯(lián)軍侵華說課稿
4,教師重點點撥以下幾個問題⑴廊坊戰(zhàn)役:義和團浴血奮戰(zhàn),對敵人毫不退縮, 其勝利，挫敗了西摩爾聯(lián)軍進犯北京的計劃，沉重打擊了侵略者的氣焰，粉碎了所謂“西方軍隊無敵”的神話。這是對學生進行愛國主義的重要素材之一，教師重點點撥突出其情感教育的重要作用。⑵讓學生（閱讀教材小字和材料，結合插圖，認清八國聯(lián)軍對中國人民犯下的滔天罪行。）并讓學生分組探討自己的看法,一方面培養(yǎng)學生的語言表訴能力,另一方面通過學生的訴說激發(fā)學生的愛國情感,樹立落后就要挨打的觀念.⑶指導學生通過對條約主要內容進行了分析，并自然得出結論：清政府完全成為帝國主義統(tǒng)治中國的工具，中國完全陷入半殖民地半封建社會。讓學生逐步學會分析和歸納能力(4)進行拓展訓練出示中國近代史上列強的大規(guī)模的侵華戰(zhàn)爭和中國人民的反抗斗爭
人教版高中英語必修4Women of achievement說課稿4篇
Good morning, distinguished judges:It’s my honor to talk about my teaching ideas with you. Today my topic is Women of Achievement. My presentation consists of six parts: the analysis of teaching material and student, teaching aims, key and difficult points, teaching and studying method, teaching procedures and blackboard design.First, let’s focus on the analysis of teaching material. This lesson is from New Senior English for China Student’s Book 4 Unit 1, the reading part. The main topic of the passage is the introduction of a student of Africanwildlife. After this lesson, the students will learn more information about her studying chimps in Africa, and their reading and speaking abilities can be developed as well.The next part is the analysis of students. My students are in senior high students. They have learnt English for many years, they’ve known many words and sentences, but their speaking and reading abilities are still not very good. So I will practice their speaking and reading abilities through different exercises.According to the New Standard Curriculum and the present situation, I set the teaching aims as follows: firstly, knowledge aims. Students can grasp some new words, such as worthwhile, move off. Moreover, students can understand the content of the passage and get familiar with the topic of studying chimps in wildlife. Secondly, ability aims. Students can use reading strategies such as skimming and scanning in reading process. Thirdly, emotional aims. Students can have the awareness of protecting animals and care about animals.Based on the above analysis, the key point of this lesson is to get the main idea and the detailed information from the passage; the difficult point is to talk about the wildlife protection and use reading strategies.
人教版高中英語必修4Body Language說課稿4篇
Textbook: Senior English for China (Book 4), by Liu Daoyi Time Allotment: 1 period (40 minutes)Date: March 20, 2014Teaching aids: blackboard, Multi-media, Power Point, chalk I. Text Analysis （教材分析）This unit is about body language, and the text selected in the reading part demonstrates the difference and similarity of body language in many parts of the world. Through learning this passage, students are required to raise their awareness of using body language in different parts of the world. As body language is closely related to our daily life, it is easy to arouse students’ interest in learning this text. Reading skills and speaking training are designed around the text.II. Teaching Objectives （教學目標）By the end of the lesson, students will be able to:1. Language Skill Objective（語言技能目標）: develop reading ability （skimming and scanning）as well as speaking ability.2. Cultural Knowledge Objective（文化知識目標）: know about the cultural differences of using body language.3. Affective Objective（情感目標）: increase students’ awareness of using body language correctly in different cultures. III.Teaching Focuses and Difficulties（教學重點和難點）1. Teaching Focuses（教學重點）: the difference and similarity of body language in many parts of the world.2. Teaching Difficulties（教學難點）: develop students’ reading abilities of skimming and scanning and ask the students to show their opinions with fluent English.
人教版高中英語必修4A taste of English Humor說課稿3篇
Then I would ask them to think of a funny English or Chinese and tell it to partners. While telling stories, they can use expressions and some acting to help make the story funny. 5 minutes would be given to do this.Those stories they told there will be the material for their writing. Soletting them tell it at first is helpful. And they can make a difference between telling a funny story and writing it down. Generally speaking, it is difficult forstudents to write well because they don’t know what to write and how to write. Asking them to tell their own stories at first can help them come up with what to write.After their telling, I would invite someone to share his/her story with all of us and I would write it down on the blackboard.This example story would be used as a sample to illustrate the format of funny story. Different from a story from teacher or textbook, a story from students can obviously become a interesting material to draw students’ attention.Then I would ask the whole class to put this story into several parts. It might be a little bit difficult for them. So I would ask them to find out whether all the sentences are necessary. After delete some sentences, there are 6 sentences left behind. Then they can easily put them into three parts. After interaction with students, I would teach them the right terms for each part and conclude the format of funny story.This step is the key and difficult point in my lesson. So I mainly usetask-based teaching method in this part and the task for students was divided into several stages. With the separated difficult level, students can find there are usually three parts in writing. They can also learn to write without the unnecessary parts in the process of analyzing. And then I wouldn’t rush to tell them the right terms to them directly. Instead, I would ask them to name them by their own. A confused mind is better for acquiring knowledge.While-writing:Then I would give students 7 minutes to write down this story, without other requirements.With all the preparations in pre-writing, students’ difficulties were cleared. So it would be much easier for them to write down the story within 7 minutes. There are no other requirements because students’ first writing is actually a drafting. It would be revise and edit several times later. Writing, as a skill
人教版高中英語必修3Canada-the true north說課稿4篇
Good afternoon, teachers, It’s my great pleasure to be here sharing my lesson with you.The content of my lesson is Senior English Book 3 Unit 5 Canada —— “The true North”.I’ll be ready to begin this lesson from five parts. Analysis of the teaching material,the teaching methods,the studying methods, the teaching procedure,and Blackboard design.First, let me talk about the teaching material.Part 1 Teaching Material:This unit is about the introduction of Canada. By studying of this unit,we’ll enable the students to learn the geography, population, main cities, and natural beauty, natural resources of Canada. Through the training of the unit, it also requires students to learn some Language skills such as the expressions of position and emotions.So it plays an important part in the English teaching in this book.After studying the teaching material and analyzing the rule of children’s growing of mind,I think the teaching aims are the followings:1.Knowledge objects:(1) make the students learn some new words and phrases(2) make the students understand the content of the lesson.2.Ability objects:(1)To develop the Ss’ abilities of listening, speaking, reading and writing. Especially reading and speaking ability.(2) learn to talk about the characters of Canada in English(3)To train the Ss’ ability of working in pairs.3.Emotion objects:(1)Enable students to understand the characters of Canada..(2)Stimulate Ss to work hard to make China stronger.Part 2 Teaching Methods:I think helping students learn to master new words and phrases and improve the students’ reading and speaking ability is import and the difficult.According to the analysis of the teaching material and the import points and the difficult points,I will use the following teaching methods : question-guiding approach; fast-reading and careful reading; multi-media teaching methods; discussion
人教版高中英語必修4Theme parks說課稿3篇
The oldest and the most popular park in the worldenjoy the exciting activities thereget close to the life-size cartoon characters like Mickey Mouse and Donald Duck Step 3 Pre-reading1.What do you suppose a theme park is ?2.What do you think you can see in a theme park?(1.It is a kind of amusement park which has a certain theme – that the whole park is based on. 2.buildings, castles, statues, rare animals and birds, and so on.) Step 4 Reading ----- Theme Parks –---- Fun and More Than Fun1.Predict : Read the title and the pictures on P. 34 and PredictWhat is the meaning of the title “Theme Park – Fun and more than fun”?(The title means that theme parks are fun to visit, but that they can also be educational and can offer useful information.)2.Skimming Fast read and answer:What activities can we take in a theme park?Amusement park: Bumper car Merry-go-round slide bungee jumping Free-fall rides Horror films Pirate ship Ferris wheel roller coaster3.Scanning Read again and you will find various theme parks are mentioned in the passage . Then what are they ?Theme parks: Sports theme park History theme park Culture theme park Marine or Ocean theme Park Future park Science theme park Disneyland4.Careful reading and find the main idea of each paragraph:THEME PARKS---- entertaining/ educationalPara.1 Traditional parks are places to go for relaxation and to have time away from our busy lives.Para.2 Theme parks are different They’re large and full of things to do, see and buy.Para.3 Theme parks are built around a single idea or theme. One example is a sports park.Para.4 Another kind of theme park is historical more and cultural and can be educational.Para.5 Disneylandwas the first theme park. It is based on the fantasy life and characters of Disney’s films.Para.6 Some examples of educational theme parks include sea world parks and science parks.
人教版高中英語必修3Healthy Eating說課稿4篇
Language learning needs a context, which can help the learners to understand the language and then can product comprehensible output, so computer has the advantages to make the materials attractive.Part 3 Learning MethodsTask-based, self-dependent and cooperative learningPart 4 Teaching ProcedureStep One Lead-in“Interest is the best teacher.” Therefore, at the very beginning of the class, I should spark the students’ mind to focus on the centre topic “the band”. I’ll show some pictures of food to attract their attention and then bring some questions.Question:What kind of food they like?What should go into a good meal?The answers must relate to the diet. After this, the students will be eager to know something about a balance diet and this is the very time to naturally lead the class into Step 2Step 2 Reading for information: skimming and scanning In this step, I use Task-based Language Teaching method, which can give students a clear and specific purpose while skimming and scanning the context.Task 1 General ideaThe students will be asked to just glance at the title and the pictures of the passage, and then guess what they will read in the text. And they’ll be divided into groups of four to have a discussion.The purpose is to inspire the students to read actively, not passively. In addition, the task is to develop the students’ reading skill by making prediction and to encourage the students to express their thoughts in English and cooperate with each other.Task 2 Main idea of each paragraphCooperative learning can raise the students’ interest and create an atmosphere of achievement. Based on this theory, I divide the whole class into 4 groups to skim the whole text and get the main idea of each paragraph.
人教版高中英語必修5The United Kingdom說課稿4篇
Teaching Aims:Knowledge 1. Get the students to learn the useful new words and expressions in this section. Aims:2. Let the students learn about how the UK was formed and the four groups of invaders.1. Develop students’ reading ability and let them learn different Ability reading skills. Aims:2. Enable students to learn to talk about the United Kingdom and the Union Jack Emotional 1. Let students know more about the UK2. Develop students’ sense of cooperative learning Aims:Teaching Important Points:1. Let the students learn about the countries of the United Kingdom and the Union Jack2. Get the students to read the passage and know about how the UK was formed and the four groups of invaders.3. Have the students learn different reading skills.Teaching Difficult Ponts:1. Develop students’ reading ability.2. Enable students to talk about the United Kingdom and the Union Jack.3. Let students learn how the UK was formed geographically and historically.Teaching Methods:Showing pictures, asking, exercising, listening, reading etc.Teaching Aids:A computer,a projector and a blackboard.Teaching Procedures: 1) Show a map of the world, ask students the following questions:Where is the UK?What’s the full name of the UK?2) Ask the students work in pairs to do the quiz on Page 9.Do you want to test how many things you know about the United Kingdom? Let’s have a small test.Using the map on P9, students answer the following questions:?How many countries does the UK consist of? What are they??England is divided into three main areas. Do you know what they are? 1) Scanning (10Minutes )Let the students hold the questions asked in pre-reading and read the passagequickly and then let them do the following exercise.Join lines to the right answer.