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新人教版高中英語必修2Unit 3 The Internet-Discovering Useful Structure教案一
This unit is about the Internet, which has a great influence to our humans and our lives. During the Listening & Speaking & Talking and Reading and Thinking section, the influence in examples has been shown. Thus, use the Present Perfect Tense is appropriate. However, in order to show the justice or weaken the doer of the behavior/action, it’s better to use the Present Perfect Passive Voice than the Present Perfect Tense. Besides, having learned to use the Present Perfect Passive Voice, students can beautify their language in their writing. 1. Learn the structure of the Present Perfect Passive Voice and its functions. 2. Learn to change the sentences with the Present Perfect Passive Voice into the sentences with the Present Perfect Passive Voice. 3. Learn to write sentences with the Present Perfect Passive Voice flexibly according to the context. 1. Learn the structure of the Present Perfect Passive Voice and its functions. 2. Learn to change the sentences with the Present Perfect Passive Voice into the sentences with the Present Perfect Passive Voice. 3. Learn to write sentences with the Present Perfect Passive Voice flexibly according to the context. Step 1 Observe the following sentences, then change the sentences into passive voice.He has been selected to take part in the sports meeting．(肯定句)他已被挑選出來參加運動會。The ink has not been removed from his overcoat．(否定句)墨跡還沒有從他外套上去掉。
新人教版高中英語必修2Unit 3 The Internet-Reading For Writing教案一
⑦identity theft 身份盜竊⑧chat room 聊天室⑨draft your blog post 起草博客帖子⑩post embarrassing photos 張貼尷尬照片 【話題句式】 1. How do you stay safe online and avoid bad experiences on the Internet? 你如何在網(wǎng)上保持安全, 避免在網(wǎng)上的不良經(jīng)歷? 2. I’m not an expert, but many years as a blogger have taught me a thing or two. 我不是專家, 但作為一個博主, 我已經(jīng)學了好幾年了。 3. If you see or read something that makes you feel uncomfortable, leave the site immediately. 如果你看到或讀到一些讓你覺得不舒服的東西, 立即離開這個網(wǎng)站。4. Don’t give out your address or phone number. 別告訴別人你的地址或電話號碼。 5. Identity theft is a common and serious problem. 身份盜竊是一個常見而嚴重的問題。6. Being online is no excuse for being rude, and you don’t want to become a target for a troll or cyberbully. 上網(wǎng)并不是無禮的借口, 你也不想成為發(fā)挑釁帖子的人或網(wǎng)絡惡霸的目標。 7. Trolls often use several false names so that they can stay on a site. 發(fā)挑釁帖子的人經(jīng)常使用幾個假名, 這樣他們就可以留在一個網(wǎng)站上。8. However, the more polite you are, the less likely it is you will be attacked. 然而, 你越有禮貌, 你被攻擊的可能性就越小。
人教版高中語文必修2《荷塘月色》教案3篇
請問，作者究竟聽到歌聲沒有？”學生回答：“沒有?！薄斑@里是比喻，因為這里用得是‘仿佛’一詞……”對，是比喻。也就是說，作者是用歌聲來比喻荷香，是吧？“但是，“荷香與歌聲有什么可比的共同點嗎？”“荷香與歌聲都是斷斷續(xù)續(xù)、若有若無的?！薄岸译鼥V朧的?！薄皩Α！昂上愫透杪暥际恰|縷’的、‘渺?！?。這是比喻。這是一種特殊的比喻，錢鐘書先生把它叫做‘通感’。人們通過視覺、聽覺、觸覺、味覺、嗅覺等五官感知外界事物時，在一般情況下，彼此不能交錯；但在特殊情況下，五官功能卻能出現(xiàn)互相轉(zhuǎn)化、彼此溝通的現(xiàn)象叫“通感”，也叫“移覺”。舉幾個例子來說明：詩人艾青曾寫詩這樣描繪日本著名指揮家小澤征爾：‘你的耳朵在偵察，你的眼睛在傾聽……’這也是通感。又如：“那笛聲里有故鄉(xiāng)綠色平原上青草的香味，有四月的龍眼花的香味，有太陽的光明?！保üL《葉笛》）
人教版高中語文必修3《蜀道難》教案2篇
【明確】“一夫當關(guān)，萬夫莫開”言劍閣有易守難攻的險要形勢，暗示中央朝廷的部隊很不容易打進來，因而野心家可以據(jù)險發(fā)動叛亂，“化為狼與豺”，搞地方割據(jù)。如果割據(jù)勢力之間出現(xiàn)矛盾沖突，難免要發(fā)生混戰(zhàn)，結(jié)果必定是“殺人如麻”。詩人這番預言在十多年后就得到了證實：從上元二年到大歷初即有段子璋、徐知道、崔旰等人相繼發(fā)動叛亂。詩人的意圖是要嚴防野心家發(fā)難。詩人從劍閣的險要引出對政治形勢的描寫。他化用西晉張載《劍閣銘》中形勝之地，匪親勿居的語句，目的在于勸人引以為鑒戒，警惕戰(zhàn)亂的發(fā)生，并聯(lián)系當時的社會背景，揭露了蜀中豺狼的磨牙吮血，殺人如麻，這既是描寫蜀道猛獸，又是影射政治黑暗的雙關(guān)語句，表達了對國事的憂慮與關(guān)切，為詩篇增加了現(xiàn)實的內(nèi)涵、深厚的意蘊。唐天寶初年，太平景象背后正潛伏著危機，后來發(fā)生的安史之亂，證明詩人的憂慮是有現(xiàn)實意義的。
人教版高中政治必修1財政收入與支出教案
（2）財政收支平衡是指當年財政收入等于支出，或收入大于支出略有節(jié)余，或支出大于收入略有赤字。（3）財政赤字是指當年財政支出大于財政收入的部分。赤字意味著要靠借債過日子，有可能導致社會總供給與總需求不平衡，引發(fā)通貨膨脹。必須把財政赤字控制在一定范圍之內(nèi)。教師活動：請同學們思考教材75頁虛框內(nèi)問題。學生活動：閱讀課本，認真思考，積極發(fā)言教師點評：發(fā)行國債可以增加財政收入，擴大政府投資，刺激消費需求，促進經(jīng)濟發(fā)展。但是國債發(fā)行規(guī)模過大，會增加政府還債負擔，不利于經(jīng)濟的長期穩(wěn)定發(fā)展。在經(jīng)濟生活中，國家可以通過調(diào)整財政收入支出控制經(jīng)濟運行。當經(jīng)濟增長緩慢時，采取積極的財政政策，增加經(jīng)濟建設支出，減少稅收，以刺激需求，拉動經(jīng)濟增長。反之，當經(jīng)濟發(fā)展過熱時，采取緊縮性財政政策，減少財政支出，增加稅收，以抑制社會需求，降低通貨膨脹率，給經(jīng)濟降溫。
人教版高中政治必修4價值與價值觀精品教案
一、教材分析我們使用的是人教版第四冊《生活與哲學》教材，本框?qū)儆诘谒膯卧谑n第一框題。其內(nèi)容主要分兩目，第一目主要介紹價值的含義、人是社會一切財富的創(chuàng)造者、人的價值在于創(chuàng)造價值和對社會的責任和貢獻，以及對一個人的評價主要看他的貢獻等內(nèi)容。第二目主要介紹價值觀的導向作用，內(nèi)容包括價值觀的含義、價值觀對人們認識世界和改造世界的活動具有導向作用以及對人生道路的選擇具有導向作用。二、教學目標知識目標：1、識記價值和價值觀的基本含義；價值觀的導向作用。2、理解人的價值是什么？如何評價人的價值。3、運用所學知識及相關(guān)哲學原理，分析物的價值和人的價值的 不同，從中加深對人的價值的理解評論分析為什么對一個人的評價要看他的貢獻，而不是索取了多少。
新人教版高中英語必修2Unit 1 Cultural Heritage-Discovering Useful Structure教案二
This theme of the part is “ Describe people or things in greater detail”. Students have learned the grammar(restrictive relative clauses) in Book 1, and further review and consolidate its structure “prep+relative pronouns(which/whom)” and the relative adverbs(when, where and why), besides students should understand its form, meaning and functions. In this section, students should be able to express the grammar correctly in daily communication and in the writing. 1. Review the basic usages of relative pronouns and adverbs of attributive clauses . 2. Learn to use some special cases about restrictive relative clauses.3. Learn to write sentences with restrictive relative clauses flexibly according to the context.1. Review the basic usages of relative pronouns and adverbs of attributive clauses .2. Learn to use some special cases about restrictive relative clauses.3. Learn tow rite sentences with restrictive relative clauses flexibly according to the context.Step 1. Observe the following sentences, and mark the relative pronouns and the adverbs. 1. After listening to the scientists who had studied the problems, and citizens who lived near the dam, the government turned to the United Nations for help.2. Temples and other cultural sites were taken down piece by piece, and then moved and put back together again in a place where they were safe from the water.Step 2 PracticePlease complete these sentences with relative pronouns and relative adverbs and answer the following questions.Questions: 1. What is the head noun ?2. What relative words should be used ?3. What elements do they act in these sentences ?
新人教版高中英語必修2Unit 2 Wildlife Protection-Discovering Useful Structure教案二
2．表示現(xiàn)階段正在進行的被動動作(該動作在說話的瞬間未必正在進行)。Many interesting experiments are being carried out these days.(說話時，并不一定正在進行)3．表示一種經(jīng)常性的被動行為，常和always，constantly 等表示頻度的副詞連用，這種用法常常帶有贊揚或厭惡的感情色彩。He is always being praised by the leader.4．表示按計劃或安排主語將要承受謂語動詞所表示的動作(僅限于少數(shù)及物動詞)。A party is being held tonight.Step 4 Special cases1.像take care of, look after, talk about, think of等動詞與介詞構(gòu)成的短語用于現(xiàn)在進行時的被動語態(tài)時, 其中的介詞不可省略。The ways to stop illegally hunting are being talked about. 2．可與部分情態(tài)動詞連用，表示對正在發(fā)生的事情的推測。She may be being punished by her mother.3．有時可表示按計劃或安排將要進行的一個被動動作。A celebration is being held this weekend for his success.4．某些表示“狀態(tài)、心理活動、存在”等的動詞，如have，want，need，love，一般不用現(xiàn)在進行時的被動語態(tài)，而常用一般現(xiàn)在時的被動語態(tài)。With the population increasing，more land is needed.5．“be＋under/in＋n.”可表示現(xiàn)在進行時的被動意義。My computer is under repair.＝My computer is being repaired.
新人教版高中英語必修2Unit 2 Wildlife Protection-Reading and Thinking教案二
The theme of this unit is human and nature, focusing on the theme of wildlife protection. Nature is a complex ecosystem, in which there are delicate balance between animals and plants. Because of the role of the food chain, the extinction of one species will produce influence, causing a series of chain reaction. Large scale extinction of species will have a serious and even irreversible impact on the ecosystem, resulting in immeasurable losses. Therefore, it is of great significance to protect wild species. To protect wild species is to protect human beings themselves. The motto of this unit is "when the buying stops, the killing can too,” which is a public service advertising slogan to protect wildlife. It tells people that every rhinoceros horn, every fur, every bowl of shark fin soup, every Ivory product, and every tiger bone product, etc. consumed by human beings, are innocent wild animals slaughtered behind them. The mission of wild aid is to ban illegal trade in endangered wildlife and mitigate climate change. It aims to educate the public to reduce the consumption demand for endangered wildlife products through public publicity and improve the awareness of environmental protection.1. Improve the awareness of wildlife protection by acquiring the knowledge of wildlife protection.2. Focus on environmental protection and protection of all lives.3. Analysis of the living environment of wild animals with appropriate thinking mode.4. Skillfully use the vocabulary and grammar knowledge of this unit to cultivate self-study ability according to the unit content5. Develop cooperative learning ability through discussion and other ways1. Enable the Ss to talk about the current situation of wild animals.2. Guide the Ss to summarize the main idea of each paragraph as well as the main idea of the text.
新人教版高中英語必修2Unit 4 History and Traditions-Discovering Useful Structure教案二
This teaching period mainly deals with grammar: The past participle is used as attributive and objective complement.1. Guide students to review the basic usages of the past participle used as attributive and objective complement.2. Lead students to learn to use some special cases concerning the past participle used as attributive and objective complement flexibly.3. Strengthen students’ great interest in grammar learning.1. Help students to appreciate the function of the past participle used as attributive and objective complement.2. Instruct students to write essays using the past participle used as attributive and objective complement.Step1:溫故而知新。Analyze the underlined phrases and then sum up the common usages of the past participles.1．(教材P41)They had castles built(build) all around England, and made changes to the legal system．2．(教材P42)They use the same flag, known(know) as the Union Jack，．．．3．(教材P42)Judy and I had our car parked(park) in an underground car park near Trafalgar Square, where we could get our car battery charged(charge)．Common points: f the past participle used as attributive and objective complement.Step 2:過去分詞作定語時的意義1．及物動詞的過去分詞作定語，在語態(tài)上表示被動；在時間上，常表示動作已經(jīng)發(fā)生或完成，有時也不表示時間性。Our teacher watched us doing the experiment and gave us a satisfied smile at last．我們的老師看著我們做實驗，最后給了我們一個滿意的微笑。The plan put forward at the meeting will be carried out soon．會上提出的計劃將很快被執(zhí)行。2．不及物動詞的過去分詞作定語，它不表示被動意義，只強調(diào)動作完成。Many little kids like gathering fallen leaves in the yard．
新人教版高中英語必修2Unit 5 Music-Discovering Useful Structures教案二
4. When he got absorbed in his world of music, he felt as if he could “see” the beauty of the world around him, like he had in his previous life.P·P as adverbial: _________________________________________________________________.Function: _______________________________________________________________________.Step 5 Solid Complete the passage with the words in brackets in their correct forms.Well known as a successful band, the Impact members show quite a few striking qualities. They never ever give up. When _____________(question) by the media, they are not _____________(discourage) and practise even harder. They are improving themselves by attending several master training class. They are united. _____________(fill with) team spirit, they act as a whole, always aiming for glory. Step 6 Difference and similarity from -ingObserve the following examples.1. He went out, shutting the door behind him.=He went out, ________________________________________________________.2. Not knowing what to do, he went to his parents for help.=__________________________________________, he went to his parents for help.Similarity: _______________________________________________________________________________________________________________________________________________________.Difference : _______________________________________________________________________________________________________________________________________________________.Step Practice1. ________ in a hurry, this article was not so good. 因為寫得匆忙, 這篇文章不是很好。2. ________ carefully, he found something he hadn’t known before. 他仔細讀書時, 發(fā)現(xiàn)了一些從前不知道的東西。3. ________ why he did it, the monitor said it was his duty. 當被問及他為什么要這么做時, 班長說這是他的職責
新人教版高中英語必修2Unit 5 Music-Reading for Writing教案二
The Internet celebrity Gao Yifeng. Years ago, he owned 5 companies and the staffs over 1,000, but during the economy crisis, he became nothing but debt. He was so worried that his hair became white overnight. There was a time when he wanted to killed himself. But after listening to the song Start Over by Liu Huan, he decided to cheer himself up. He started a steamed bun shop and gradually became a national chain shops. Now he became successful again.Walter Haddon said, “Music is the medicine of a troubled mind.” Music contains such a pleasant and inspiring force. Music gave him courage and bravery. When he listened to the song, it made his spirit fly like a kite in the wind. Music gave him strength and brought him relief. It was the rock I leant on to become strong and to get through those hard times. I hope none of us have to go through the same kind of suffering that he did. At the same time, we all go through various periods when we feel sad or alone. During those times, music can help us in the same way that it helped him. I hope we all will somehow begin to treasure music and make it a part of our life. Thank you for your listening !5.Revise your writing each other.Does he/she explain how music has changed his/her/someone else’s life?Are some of the rhetorical devices included and used properly ?Does he/she talk about how music makes him/her/someone feel?Is the first word in each sentences capitalised?Does he/she use correct punctuation ?
高中數(shù)學人教版必修二直線的點斜式方程教案
【教學目標】知識目標：理解直線的點斜式方程、斜截式方程、橫截距、縱截距的概念；掌握直線的點斜式方程、斜截式方程的確定．能力目標：通過求解直線的點斜式方程和斜截式方程，培養(yǎng)學生的數(shù)學思維能力與數(shù)形結(jié)合的數(shù)學思想．情感目標：通過學習直線的點斜式方程和斜截式方程，體會數(shù)形結(jié)合的直觀感受．【教學重點】直線的點斜式方程、斜截式方程的確定．【教學難點】直線的點斜式方程、斜截式方程的確定．
新人教版高中英語必修2Unit 2 Wildlife Protection-Reading for Writing教案二
This lesson aims at making a poster about protecting wildlife after reading some posters. During reading students are guided to understand the content and try to summarize the posters with one sentence. Then students are guided to try to make a poster about protecting wildlife.1. Read the two posters and try to understand the summary sentences.2. Look at the two posters and try to understand what emotions they express.3. Try to summarize the features of posters4. Try to make a poster about wildlife.1. Look at the two posters and try to understand what emotions they express.2. Try to summarize the features of posters3. Try to make a poster about wildlife.Step 1 Lead inLook at the the posters on the textbook and ask:Which emotions do the posters communicate ?Step 2 Read the poster and answer the questions.1. What do you think of the animals in the poster on the left ?I think it is frightening and ugly.2. Why do we should protect the ugly animals ?All species--the good, the bad, and the ugly-- should be treated equally.The world needs all kinds--without variety, our planet cannot survive.3. Why are billions of trees being cut down every year ?To make paper for humans.4. What result will be lead to after the trees are cut down ?A lost of animal homes are being destroyed./The habitat of wildlife is being destroyed.Step 3 Find the feature of posters1. What does each poster use to stir up emotions ?On the left, it makes us a little frightened and it looks a little ugly, but it can activate our curiosity--What is it? And What is wrong with it?On the right, it makes us feel a little sad and want to protect them.
新人教版高中英語必修2Unit 1 Cultural Heritage-Reading and Thinking教案二
1. This section focuses on "Understanding how a problem was solved”, which is aimed to guide students to analyze and discuss the challenges and problems faced by cultural heritage protection during the construction of Aswan Dam, as well as the solutions. On the basis of understanding, students should pay attention to the key role of international cooperation in solving problems, and attach importance to the balance and coordination between cultural heritage protection and social and economic development. Students are encouraged to face challenges actively, be good at cooperation, and make continuous efforts to find reasonable ways and means to solve problems.2. Enable students to understand the main information and text structure of the reading text;3. Motivate students to use the reading strategy "make a timeline" according to the appropriate text genre;4. Enable students to understand how a problem was solved;5. Enable students to understand the value of protecting cultural heritage by teamwork and global community;1. Guide students to pay attention to reading strategies, such as prediction, self-questioning and scanning.2. Help students sort out the topic language about protecting cultural relics and understand the narrative characteristics of "time-event" in illustrative style3. Lead students to understand the value of protecting cultural heritage by teamwork and global community;
新人教版高中英語必修2Unit 4 History and Traditions-Reading and Thinking教案二
Step 5 While reading---Task 3Read the text again and answer the following questions.Q1: How many countries does the UK consist of ?4 Q2: What are the four countries of the United Kingdom?England, Wales, Scotland and Northern Ireland Q3: Which two were the first to be joined together ?England and WalesQ4: What are the two chief advantages of studying the history of a country ?The first one is to help you understand more about the country and its traditions.The second one is to make visiting it more enjoyable.Q5: What’s the author’s attitude towards studying the history ?Supportive/positiveStep 6 Post reading---Retell the textThe United Kingdom, Great Britain, Britain, England—many people are confused by (1)_____ these different names mean. In the 16th century, the nearby country of Wales (2) __________(join) to the Kingdom of England. In the 19 th century, the Kingdom of Ireland was added to create the United Kingdom of Great Britain and Ireland. Finally, the southern part of Ireland (3) ______ (break) away from the UK, which resulted in the full name we have today. However, most people just use the (4)_________(shorten) name: the UK. The four countries (5)__________ belong to the United Kingdom work together in some areas. There were four sets of invaders and the last group were the Normans. They had castles (6)_________(build) all around England and made changes (7)__________ the legal system. Studying the history of the country will make your visit much more (8)_________(enjoy). The capital city London is (9)___ ancient port city that has a history (10)______(date) back to Roman times. 1. what 2.was joined 3.broke 4.shortened 5.that 6. built 7.to 8.enjoyable 9.an 10.dating Step 6 Homework
新人教版高中英語必修2Unit 4 History and Traditions-Listening＆Speaking＆Talking教案二
Listening and Speaking introduces the topic of “Take part in a youth project”. The listening text is an interview about "sharing views on historical sites". Through listening to a dialogue between Chinese and foreign students on the way to the Confucius Temple, students can understand their views on the Confucius Temple, Confucius, Confucius' descendants and Confucius' educational thoughts, so as to realize and think about the profound influence of Confucius and his thoughts on Chinese historical tradition. At the same time, the dialogue naturally integrates English idioms and mentions Shakespeare, the British playwright, so as to provide language materials and context for students to understand English idioms and related cultural allusions, as well as to compare Chinese and foreign cultures, which is helpful for students to understand and express the language such as history, tradition, culture and custom significant impact.Text analysis: listening text is a dialogue between a British student and a Chinese student when he goes to the Confucius Temple. When William, a British student, visited the Confucius Temple, he asked Xiao Kong, a Chinese student, for directions. Xiao Kong was just going to the Confucius Temple to meet with the members of the research group, so they went together and exchanged their views on the Confucius Temple, Confucius, Confucius' descendants and Confucius' educational thoughts. From the perspective of foreign tourists, this paper describes their thoughts on Confucius, the great son of Confucius, who had a profound impact on Chinese history and cultural tradition, and his education.Listening and Talking introduces a visit to a historic tourist destination. Tourism is a common way to understand a country's history, culture, and customs and so on. Students listen to the dialogue between Xiao Yan, a youth hostel Usher, and Paul, a backpacker, to learn about Pingyao's famous historical and cultural attractions and Paul's travel experience and experience as a foreign tourist.
新人教版高中英語必修2Unit 5 Music-Reading and Thinking教案二
1. Get basic information about Eric; read deeply to understand the history and development of the virtual choir.2. Understand what the function of the virtual choir is and how to make a virtual choir.3. Understand the meaning of some languages in the context of the text through question guidance, such as “Many people do not have close friends or contacts who have the same interest in music.” and so on.Step 1 Leading-in1. Answer the following questions.Q1：Do you know the Apps like Tik Tok and Quick Hand?Q2: Do you want to make a Tik Tok video or a Quick Hand video?2. Play a Tik Tok video Step 2: Understanding the title Q1：What does the title mean ?Q2: Is the article a narration or exposition? Why? Q3: Can you change the title ? If you can, what is the title?Step 3: Scanning the whole text and getting the basic information1. Answer the following questions.Q1：Who came up with the idea for a virtual choir?Q2: Where did Eric studied the musical composition?Q3: What is his song?2. Find the main idea of each paragraph3. Deal with some new words.Step 4: Reading carefully to get detailed informationPara 1 How to make a virtual choir1. PreparationA. tools: a virtual camera; an Internet connectionB. hero/heroin: friends or some individuals who have the same interests2. Process
高中數(shù)學人教版必修二直線的點斜式方程教案
【教學重點】直線的點斜式方程、斜截式方程的確定．【教學難點】直線的點斜式方程、斜截式方程的確定．【教學過程】1、對特殊三角函數(shù)進行鞏固復習；表1 內(nèi)特殊三角函數(shù)值 不存在圖1 特殊三角形2、鞏固復習直線的傾斜角和斜率相關(guān)內(nèi)容；直線的傾斜角：，；直線的斜率： ， ；設點為直線l上的任意兩點，當時，
人教版新課標高中物理必修1彈力教案2篇
一般情況下，凡是支持物對物體的支持力，都是支持物因發(fā)生形變而對物體產(chǎn)生彈力。所以支持力的方向總是垂直于支持面而指向被支持的物體。例1：放在水平桌面上的書書由于重力的作用而壓迫桌面，使書和桌面同時發(fā)生微小形變，要恢復原狀，對桌面產(chǎn)生垂直于桌面向下的彈力f1，這就是書對桌面的壓力；桌面由于發(fā)生微小的形變，對書產(chǎn)生垂直于書面向上的彈力f2，這就是桌面對書的支持力。學生分析：靜止地放在傾斜木板上的書，書對木板的壓力和木板對書的支持力。并畫出力的示意圖。結(jié)論：壓力、支持力都是彈力。壓力的方向總是垂直于支持面而指向被壓的物體，支持力的方向總是垂直于支持面而指向被支持的物體。引導學生分析靜止時，懸繩對重物的拉力及方向。引導得出：懸掛物由于重力的作用而拉緊懸繩，使重物、懸繩同時發(fā)生微小的形變。重物由于發(fā)生微小的形變，對懸繩產(chǎn)生豎直向下的彈力f1，這是物對繩的拉力；懸繩由于發(fā)生微小形變，對物產(chǎn)生豎直向上的彈力f2，這就是繩對物體的拉力。