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新人教版高中英語必修1Unit 4 Natural Disasters-Listening and Speaking教案
【教材分析】高考聽力材料的選用非常重視語言真實性和交際性的原則，語言材料一般來源于實際生活，對話的內(nèi)容大都取材于日常生活，即衣、食、住、行、工作、學(xué)習(xí)、天氣、生活環(huán)境等話題，可分為校園、公共場所、家庭等方面，如: shopping, finding the way, doing one’s homework, seeing a doctor, making a phone call, weather report, asking for different kinds of information等。新教材的特點就是利用生活中真實文本，只是降低難度，讓學(xué)生注重語言的應(yīng)用，將是我們高考把握方向的重要因素?！窘虒W(xué)目標(biāo)與核心素養(yǎng)】學(xué)習(xí)能力目標(biāo)：在聽力當(dāng)中，學(xué)生應(yīng)該有效規(guī)劃學(xué)習(xí)方法，選擇恰當(dāng)?shù)牟呗耘c方法。這節(jié)課的訓(xùn)練目標(biāo)是讓學(xué)生有正確的預(yù)測和抓住問題的關(guān)鍵信息，從而用心去聽來找尋關(guān)鍵信息。根據(jù)生活中實際情況和高考常見語境，我們不難發(fā)現(xiàn)提前預(yù)測和抓住題干中的w很重要，即what, where, when, why等等。
新人教版高中英語必修1Welcome Unit-Discovering Useful Structures教案
II Learn the technical terms-2.1. What can be used as “Subject, Object, Predicative, Direct Object, Indirect Object and objective complement” in a sentence?2. What can be used as “adverbial” in a sentence?3. What can be used as “verb” in a sentence?Answers to questions 1-3:1. Nouns, pronouns and appellations can be used as “Subject, Object, Predicative, Direct Object, Indirect Object and Objective Complement”. Besides, adjectives can be used as “Predicative and Objective Complement” in a sentence.2. Adverbs and prepositional phrases can be used as “Adverbial”.3. Verbs with actual meaning can be used as “Verb” in a sentence. Auxiliary verbs alone cannot be used as “Verb” in a sentence.III Learn to recognize the sentence structures.1. SV structure. For Example:(1) A bird flies.S V(2) A monkey jumps.S V(3) A fish swims.S V√ In SV structures, verbs are “intransitive verbs”.2. SVO structure. For Example:(1) A sheep eats grass.S V O(2) They like bananas.S V O(3) He wants candy.S V O√ In SVO structures, verbs are “transitive verbs”.3. SP structure. For Example:(1) This is great.S P (2) He looks well.S P (3) She became a teacher.S P √ In SP structures, Predicatives are formed by “l(fā)ink verbs” and “adjectives or nouns”.√ link verbs: be, become, grow, look, feel, taste, etc.4. SV IO DO structure. For Example:(1) He asked me a question.S V IO DO(2) Danny wrote me a letter.S V IO DO(3) Billy brought Sam a kite.S V IO DO√ In SV IO DO structures, the verbs are transitive and are followed by two objectives – pronouns or nouns as Indirect Objective, and nouns as Direct Objectives.
新人教版高中英語必修1Unit 4 Natural Disasters-Reading & Thinking教案
5. Read to get detailed information about Paragraph 5.Q1. What shows the revival of Tangshan?Q2. How can Tangshan revive itself and get up on its feet again?Q3. In times of disasters, how can we go through it?T: In times of disasters, we should unify, show the wisdom and stay positive.Step 4 Activity 4 Highlighting the theme and reflecting1. Make a summary of the text.2. Further understand the titleQ: After our learning, why do you think the earth didn’t sleep on that night?T: An earthquake happened. The people in the earthquake suffered a lot, and the people outside Tangshan were concerned about the people there a lot.3. Reflect through discussion on what can be learnt after reading.T: Disasters are powerful. Unpreparedness can be deadly. Life is weak, but if people work together to help each other, disasters can be defeated.There is no love from disaster, but we have love in the human heart.Step 5 Assignment How does the writer convey that the earthquake was deadly, and that people were helpless during the earthquake? Try to find some attractive and impressive expressions and note them down.
新人教版高中英語必修1Unit 5 Languages Around the World-Reading for Writing教案
Step 3: Read to sum upRead it again and sum up the problems of the three students, and then write down the advice that was given from others.Step 4: Work in pairs. List your learning problems in English and brainstorm some useful advice.Useful expressions ? I don't know how to…... Is a big difficulty for me. I cannot ...? You might try …. It's very important to…? I have no idea how/what .My biggest problem is .... ? I (also) have trouble with. My advice is …. This worked for me.? l cannot understand the teachers’ English in class.Step 5 Homework：為提高我校學(xué)生的英語口語水平，我們將舉辦英語演講比賽(English- speaking contest)，請你根據(jù)下面的信息，以學(xué)生會(the Students‘ Union)的名義寫一份海報，歡迎全校同學(xué)參加，屆時特邀本校美籍教師史密斯先生頒獎。? 報名時間 9月30日以前(報名:signup)? 報名地點 學(xué)生會辦公室? 比賽時間 10月9日晚7:00~9:00? 比賽地點 學(xué)校大會議室? 獎勵 前8名
新人教版高中英語必修1Welcome Unit-Reading and Thinking教案
Step 2 New WordsUse ppt to show some words from the passage.Tell the students to remember the meanings.Step3 Skimming and Thinking1. Skim the text and decide which order Han Jing follows to talk about her first day. Time order or place order?Time order2. What is Han Jing worried about before she goes to senior high school?She is worried about whether she will make new friends and if no one talks to her, what she should do.Step 4 Fast Reading1. Match the main ideas with each paragraphParagraph 1:The worries about the new school day Paragraph 2Han Jing’s first maths classParagraph 3Han Jing’s first chemistry classParagraph 4Han Jing’s feelings about her first senior school dayStep 5 Careful Reading1. Fill in the chart with the words and phrases about Han Jing’s day. Answers: Senior high school, a little nervous; Her first maths class, classmates and teachers, friendly and helpful; Chemistry lab; new; great; annoying guy; Confident; a lot to explore2. Read the text again and discuss the questions.1) Why did Han Jing feel anxious before school?Because she was a new senior high student and she was not outgoing. What was more, she was worried about whether she can make friends.2) How was her first maths class?It was difficult but the teacher was kind and friendly. 3) What happened in the chemistry class? What would you do if this happened to you? A guy next to Han Jing tried to talk with her and she couldn’t concentrate on the experiment.
新人教版高中英語必修1Welcome Unit-Reading for Writing教案
教學(xué)目標(biāo)知識目標(biāo)：讓學(xué)生更好理解如何恰當(dāng)?shù)貙懸粋€人的信息介紹，并能讓學(xué)生熟練地使用一些寫作技能。能力目標(biāo)：培養(yǎng)學(xué)生的寫作能力和團隊協(xié)作能力。情感目標(biāo)：提升學(xué)生對寫作的興趣。教學(xué)重難點 教學(xué)重點：如何能讓學(xué)生更好地理解個人信息介紹。教學(xué)難點：如何能讓學(xué)生通過適當(dāng)?shù)厥褂靡恍懽骷寄軄韺懸黄^好的個人信息介紹。教學(xué)準(zhǔn)備 多媒體、黑板、粉筆一、Pre-class1. Greetings2. Leading-inAsk students how to write a profile. What kinds of aspects should be included? The teacher asks students to discuss the topic with each other and put forward to much more ideas about the answer.二、While-class1. The teacher lets students to read the student profiles on Page 8 silently and then asks students to discuss the questions below.1. What is Ann like? How do you know?2. What are Thando’s hobbies?3. Where does Thando come from?4. What is Thando’s dream?5. What does “You will never see me without a book or a pen” mean?
人教版高中語文必修4《柳永詞兩首》教案
（一）上片：描寫杭州的自然風(fēng)光和都市的繁華“東南形勝，三吳都會，錢塘自古繁華”，“東南形勝”，是從地理條件、自然條件著筆寫的。杭州地處東南，地理位置很重要，風(fēng)景很優(yōu)美，故曰：“形勝”?！叭齾嵌紩?，是從社會條件著筆寫的。它是三吳地區(qū)的重要都市，那里人眾薈萃，財貨聚集，故曰：“都會”。“錢塘自古繁華”，這一句是對前兩句的總結(jié)，因為杭州具有這些特殊條件，所以“自古繁華”。下面就對“形勝”、“都會”和“自古繁華”進行鋪敘。“煙柳畫橋，風(fēng)簾翠幕，參差十萬人家”是對“三吳都會”的展開描寫。“云樹繞堤沙。怒濤卷霜雪，天塹無涯”是對“東南形勝”的展開描寫。這里選擇了錢塘江岸和江潮兩種景物來寫。“市列珠璣，戶盈羅綺，競豪奢”是對“錢塘自古繁華”的展開描寫。描寫了兩個方面：一是商業(yè)貿(mào)易情況——“市列珠璣”，只用市場上的珍寶，代表了商業(yè)的豐富、商業(yè)的繁榮；二是衣著情況——“戶盈羅綺”,家家披羅著錦?！案偤郎荨?，又總括杭州的種種繁華景象。
新人教版高中英語必修1Unit 1 Teenage Life-Reading for Writing教案
【教材分析】This teaching period mainly deals with reading for writing a letter of advice. Students are expected to learn the knowledge about how to write a suggestion letter. The teacher is expected to enable students to master some writing skills concerning suggestion letters and learn to write one.【教學(xué)目標(biāo)與核心素養(yǎng)】1. Get students to have a good understanding of how to write a suggestion letter properly.2. Enable students to use some writing skills flexibly.3. Develop students’ writing and cooperating abilities.4. Strengthen students’ great interest in writing discourses.【教學(xué)重難點】1. How to enable students to have a good understanding of the skills of writing a suggestion letter2.How to enable students to write a good recommendation letter using some writing skills properly.【教學(xué)過程】Step 1: Lead in Begin the class with the lead-in questions: how to write a letter for advice? What kinds of aspects should be included? It is strongly recommended that the teacher should ask students to discuss the topic freely with their partners and brainstorm some ideas concerning the topic. In this way, students can come up with more ideas and avoid being nervous at the beginning of the class.Step 2: Read to discover details concerning advice letters’ writing style.The teacher is expected to ask students to read a letter offering some advice on page 18 silently and then request students to discuss the questions below.
新人教版高中英語必修1Unit 3 Sports and Fitness-Reading for Writing教案
Then have them write a short paragraph to describe and explain their changes. After that, get the Ss to exchange their drafts with their partners and use the checklist to give feedback on their drafts, and finally revise it.Step 5 Summary of how to write a wellness book1.健康書的審題步驟：第一步：明確要求該寫作屬于經(jīng)驗分享，故要用第一人稱來寫;時態(tài)以一股現(xiàn)在時為主。第二步：確定段落該類文章可以從以下三個方面人手:Para.1首先表明寫作的目的Para.2自己的做法及心得體會Para.3表示期望及感謝第三步：提煉要點2.健康書常見句式：1) It is an honor for me to share my favorite sport with you,2) It makes me feel relaxed playing with my friends.3) It makes me rid myself of stress while playing with my friends.4) Moreover, it provides me a valuable chance to communicate with others.5) I we eat too little or too much, or if we choose the wrong food, we may become sick.6) We can do something to change the poor situation.Step 6Homework假如你的老師讓你在班級Wellness Bok上分享自己的親身經(jīng)歷及心得，請根據(jù)以下要點寫一篇80字左右的文章1. 你喜歡的運動是什么？2. 你最喜歡的原因是什么？3. 你參加鍛煉的體會。
新人教版高中英語必修1Unit 4 Natural Disasters- Reading for writing教案
①標(biāo)題——標(biāo)題應(yīng)當(dāng)簡潔明了。②導(dǎo)語——導(dǎo)語是消息開頭的第一段或第一句話，簡明扼要地揭示出消息的核心內(nèi)容。③主體——主體是消息的主要部分，要用充足的事實表現(xiàn)主題，對導(dǎo)語的內(nèi)容作進一步的展開和闡述。④結(jié)束語——通常是對全文內(nèi)容進行概括性的總結(jié)。3. 新聞報道增分句子（1）陳述事實常用的句型:①A terrible storm hit/struck ... , killing ..②It was a cool autumn night when the earthquake happened. A large number of buildings fell down and roads were destroyed, leaving a great many people homeless.地震發(fā)生在一個涼爽的秋夜。大量的建筑物倒塌，道路被毀,許多人無家可歸。③With the help of the rescue team, people who were the trapped in the flood were saved.在救援隊的幫助下，困在洪水中的人們得救了。（2）陳述觀點常用的句型:①Clearly/Obviously/In my opinion/It seemed that people were shocked.顯然/在我看來/似乎人們震驚了。②The whole city was in ruins after the earthquake.地震后整個城市成了一片廢墟。（3）揭示原因常用的句型:Because of/As a result of/Thanks to the help of the army, people who got injured were sent to the hospital immediately.
新人教版高中英語必修1Welcome Unit-Discovering Useful Structures & Listening and Talking教案
常跟雙賓語的動詞有：（需借助to的）bring, ask, hand, offer, give, lend, send, show, teach, tell, write, pass, pay, promise, return等；基本句型 五S +V + O + OC（主＋謂＋賓＋賓補）特點：動詞雖然是及物動詞，但是只跟一個賓語還不能表達(dá)完整的意思，必須加上一個補充成分來補足賓語，才能使意思完整。 判斷原則：能表達(dá)成—賓語 是…/做…注：此結(jié)構(gòu)由“主語+及物的謂語動詞+賓語+賓語補足語”構(gòu)成。賓語與賓語補足語之間有邏輯上的主謂關(guān)系或主表關(guān)系，若無賓語補足語，則句意不夠完整?？梢杂米鲑e補的有：名詞，形容詞，副詞，介詞短語，動詞不定式，分詞等。如：He considers himself an expert on the subject.他認(rèn)為自己是這門學(xué)科的專家。We must keep our classroom clean.我們必須保持教室清潔。I had my bike stolen.我的自行車被偷了。We invited him to come to our school.我們邀請他來我們學(xué)校。I beg you to keep secret what we talked here.我求你對這里所談的話保密。用it做形式賓語，而將真正的賓語放到賓語補足語的后面，以使句子結(jié)構(gòu)平衡，是英語常用的句型結(jié)構(gòu)方式。即：主語+謂語+it+賓補+真正賓語。如：We think it a good idea to go climb the mountain this Sunday.
新人教版高中英語必修1Unit 5 Languages Around the World-Reading and Thinking教案
【教材分析】本節(jié)課是高中英語第一冊的最后一個單元的閱讀和思考部分，文章難度明顯增加，體現(xiàn)在以下幾個方面：文章題材是說明文，比較難理解；話題生疏，涉及到歷史等知識；生詞量增大，而且在語境中理解詞匯的要求提高。面對這些，教師的難度和高度也要有所提升，通過探討說明順序，了解背景知識等幫助他們找到說明文閱讀的方法?！窘虒W(xué)目標(biāo)與核心素養(yǎng)】1. 文化意識目標(biāo)新課程中指出，文化意識是對中外文化的理解和對優(yōu)秀文化的認(rèn)同。文化意識的的培養(yǎng)有助于學(xué)生增加國家認(rèn)同和家國情懷，成為有文明素養(yǎng)和社會責(zé)任感的人。我們這個單元很好體現(xiàn)了這一點，通過了解漢字書寫的體系和發(fā)展，學(xué)生可以有一種文化自豪感，同時也能夠幫助學(xué)生深入挖掘這篇文章，從而想到更多和中國文化相關(guān)的方面。2. 學(xué)習(xí)能力目標(biāo)
《場景》教案
感知樂曲。1、看課件，配合舞劇畫面欣賞樂曲《場景》，感受樂曲情緒。2、介紹樂曲的相關(guān)故事情節(jié)。柴可夫斯基的《天鵝湖》取材于德國作家姆宙斯的童話《天鵝湖)和俄國民間故事《天鵝公主》，講述了一位美麗善良的公主奧杰塔被施魔法變成了天鵝，只有在夜晚，天鵝才能恢復(fù)人形。一天晚上，一位王子在湖邊發(fā)現(xiàn)了公主，并決心搭救它?！秷鼍啊繁闶窃搫〉谝荒坏慕K場音樂，給我們描繪出純潔、溫柔、憂愁、悲傷的天鵝奧杰塔形象。3、通過天鵝資料庫，討論天鵝的話題。（1）在大家心目中，天鵝是什么樣子的？（學(xué)生自由描述天鵝形象）（2）學(xué)生在天鵝資料庫了解自己最感興趣的話題。（3）指名學(xué)生相互交流。
無理數(shù)教材教案
1、舉例而生活還有類似的例子嗎？2、為了加固一個高2米、寬1米的大門，需要在對角線位置加固一條木板，設(shè)木板長為a米，a的值可能是整數(shù)嗎?a的值可能是分?jǐn)?shù)嗎？3、2.如下圖B，C是一個生活小區(qū)的兩個路口，BC長為2千米，A處是一個花園，從A到B，C兩路口的距離都是2千米，現(xiàn)要從花園到生活小區(qū)修一條最短的路，這條路的長可能是整數(shù)嗎？可能是分?jǐn)?shù)嗎？說明理由.4、上圖是由16個邊長是1的小正方形拼成，任意連接小正方形的若干個頂點，得到一些線段．試分別找出長度是有理數(shù)的線段和長度不是有理數(shù)的線段．你還能找到其他長度不是有理數(shù)的線段嗎？
《千人糕》教案
一、談話導(dǎo)入師：同學(xué)們，中國有句俗話叫“民以食為天”，你們喜歡美食嗎？（喜歡）老師也喜歡吃，不過我們可別光顧著吃，我們要認(rèn)識它，還要記住他們的名字。（課件出示米糕圖片）。1、師：看，老師給你們帶來了什么？（米糕）生活中，你們除了吃過米糕，還吃過什么糕呢？（課件出示詞語：蛋糕、雪糕、糕點。）領(lǐng)讀詞語。2、師：不論是蛋糕、雪糕，還是糕點，味道上都有一個共同點是（）？甜，是因為在里面加入了糖，（出示糖的卡片認(rèn)讀生字“糖”）課件出示生活中常見的糖的圖片，齊讀詞語。3、引導(dǎo)觀察生字“糕、糖”，發(fā)現(xiàn)共同點，引出“粉”。交流“粉”的識字方法，引出“芬、份、紛、扮”，出示詞語：粉絲、粉筆、面粉。齊讀。
人教版高中政治必修4真正的哲學(xué)都是自己時代精神上的精華精品教案
一、教材分析 《真正的哲學(xué)都是自己時代精神上的精華》是人教版高中政治必修四第3章第1框的教學(xué)內(nèi)容，主要學(xué)習(xí)哲學(xué)與時代的關(guān)系。二、教學(xué)目標(biāo)1．知識目標(biāo)：識記哲學(xué)是時代的精神上的精華；理解哲學(xué)與時代的關(guān)系。2．能力目標(biāo)：培養(yǎng)學(xué)生運用哲學(xué)理論觀察、分析、處理社會問題的能力，增強學(xué)生的時代感。3．情感、態(tài)度和價值觀目標(biāo)：培養(yǎng)學(xué)生與時俱進的思想品質(zhì)，讓學(xué)生關(guān)注時代、關(guān)注現(xiàn)實、關(guān)注生活，逐步樹立科學(xué)的世界觀、人生觀、價值觀 。三、教學(xué)重點難點哲學(xué)與時代的關(guān)系。四、學(xué)情分析本框題的內(nèi)容比較抽象，不易理解，所以講解時需要詳細(xì)。教師指導(dǎo)學(xué)生借助歷史知識進行理解。五、教學(xué)方法1．教師啟發(fā)、引導(dǎo)，學(xué)生自主閱讀、思考，討論、交流學(xué)習(xí)成果。2．學(xué)案導(dǎo)學(xué)：見后面的學(xué)案。3．新授課教學(xué)基本環(huán)節(jié)：預(yù)習(xí)檢查、總結(jié)疑惑→情境導(dǎo)入、展示目標(biāo)→合作探究、精講點撥→反思總結(jié)、當(dāng)堂檢測→發(fā)導(dǎo)學(xué)案、布置預(yù)習(xí)
能干的小手中班教案中班社會能干的我教案
1、談話導(dǎo)入，激發(fā)興趣。 師：小朋友，每個人都有自己的興趣愛好，老師也有自己的興趣和愛好，你能猜猜是什么愛好嗎? 生：自由發(fā)言 師：我想小朋友也都有自己的興趣愛好，誰愿意告訴大家呢? 生：幼兒各自說出自己的興趣愛好。 2、師幼相互分享自己的興趣愛好。A幼兒展示自己的興趣愛好。 B教師展示興趣愛好。 3、闖關(guān) 闖關(guān)游戲一：我是小小主持人
北師大初中七年級數(shù)學(xué)上冊有理數(shù)乘法的運算律教案2
分析：（1）（2）用乘法的交換、結(jié)合律；（3）（4）用分配律，4.99寫成5－0.01學(xué)生板書完成，并說明根據(jù)什么？略例3、某校體育器材室共有60個籃球。一天課外活動，有3個班級分別計劃借籃球總數(shù)的 ， 和 。請你算一算，這60個籃球夠借嗎？如果夠了，還多幾個籃球？如果不夠，還缺幾個？解：=60－30－20－15 =－5答：不夠借，還缺5個籃球。練習(xí)鞏固：第41頁1、2、7、探究活動 （1）如果2個數(shù)的積為負(fù)數(shù)，那么這2個數(shù)中有幾個負(fù)數(shù)？如果3個數(shù)的積為負(fù)數(shù)，那么這3個數(shù)中有幾個負(fù)數(shù)？4個數(shù)呢？5個數(shù)呢？6個數(shù)呢？有什么規(guī)律？ （2）逆用分配律 第42頁 5、用簡便方法計算（三）課堂小結(jié)通過本節(jié)課的學(xué)習(xí)，大家學(xué)會了什么？本節(jié)課我們探討了有理數(shù)乘法的運算律及其應(yīng)用.乘法的運算律有：乘法交換律：a×b=b×a；乘法結(jié)合律：(a×b)×c=a×(b×c);分配律：a×(b+c)=a×b+a×c.在有理數(shù)的運算中，靈活運用運算律可以簡化運算.（四）作業(yè)：課本42頁作業(yè)題
北師大初中七年級數(shù)學(xué)上冊有理數(shù)的乘方教案2
二．思考：（－2） 可以寫成－2 嗎？（ ） 可以寫成 嗎？（指名學(xué)生回答，師生共同總結(jié)：負(fù)數(shù)和分?jǐn)?shù)的乘方書寫時，一定要把整個負(fù)數(shù)和分?jǐn)?shù)用小括號括起來）三．計算：①（－2） ，②－2 ，③（- ） ，④ （叫4個學(xué)生上臺板演，其他練習(xí)本上完成，教師巡視，確保人人學(xué)得緊張高效）．（四）討論更正，合作探究1．學(xué)生自由更正，或?qū)懗霾煌夥ǎ?．評講思考：將三題①③中將底數(shù)換成為正數(shù)或0，結(jié)果有什么規(guī)律？學(xué)生總結(jié)：負(fù)數(shù)的奇次冪是負(fù)數(shù)，負(fù)數(shù)的偶次冪是正數(shù)，正數(shù)的任何次冪都是正數(shù)，0的任何正整數(shù)次冪都為0。有理數(shù)的乘方就是幾個相同因數(shù)積的運算，可以運用有理數(shù)乘方法則進行符號的確定和冪的求值．乘方的含義：①表示一種運算；②表示運算的結(jié)果．
北師大初中七年級數(shù)學(xué)上冊有理數(shù)的乘法法則教案2
討論歸納，總結(jié)出多個有理數(shù)相乘的規(guī)律：幾個不等于0的因數(shù)相乘，積的符號由負(fù)因數(shù)的個數(shù)決定。當(dāng)負(fù)因數(shù)有奇數(shù)個時，積的符號為負(fù)；當(dāng)負(fù)因數(shù)有偶數(shù)個時，積的符號為正。只要有一個因數(shù)為0，積就為0。（2）幾個不等于0的因數(shù)相乘時，積的絕對值是多少？（生：積的絕對值是這幾個因數(shù)的絕對值的乘積.）例2、計算：（1） ；（2） 分析：（1）有多個不為零的有理數(shù)相乘時，可以先確定積的符號，再把絕對值相乘；（2）若其中有一個因數(shù)為0，則積為0。解：（1） = （2） =0練習(xí)（1） ，（2） ，（3） 6、探索活動：把－6表示成兩個整數(shù)的積，有多少種可能性？把它們?nèi)繉懗鰜?。（三）課堂小結(jié)通過本節(jié)課的學(xué)習(xí)，大家學(xué)會了什么？(1)有理數(shù)的乘法法則。(2)多個不等于0的有理數(shù)相乘，積的符號由負(fù)因數(shù)的個數(shù)決定。(3)幾個數(shù)相乘時，如果有一個因數(shù)是0，則積就為0。（4）乘積是1的兩個有理數(shù)互為倒數(shù)。（四）作業(yè)：課本作業(yè)題