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新人教版高中英语必修3Unit 1 Festivals and Celebrations-Reading and Thinking教学设计
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.
新人教版高中英语必修3Unit 3 Diverse Cultures-Reading for Writing教学设计
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.
新人教版高中英语必修3Unit 3 Diverse Cultures-Reading and Thinking教学设计
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
新人教版高中英语必修3Unit 4 Space Exploration-Listening&Speaking&Talking教学设计一
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.
新人教版高中英语必修3Unit 4 Space Exploration-Listening&Speaking＆Talking教学设计二
The themes of this part are “Talk about how to become an astronaut” and “Talk about life in space”. As Neil Armstrong said “Mystery creates wonder and wonder is the basis of man’s desire to understand. Space is difficult for human to reach, therefore, humans are full of wonders about it. However, if wanting to achieve the dream of reaching the Moon, some of our human should work hard to be an astronaut at first. Part A(Talk about how to become an astronaut) is a radio interview in a radio studio, where the host asked the Chinese astronauts about his story how to become an astronaut. Yang Liwei told his dreamed to be an astronaut since childhood. Then he worked hard to get into college at 22. The next 10 years, he gradually became an experienced pilot. At the same time, to be an astronaut, he had to study hard English, science and astronomy and trained hard to keep in good physical and mental health and to practise using space equipment. Part B (Talk about life in space) is also an interview with the astronaut Brown, who is back on the earth. The host Max asked about his space life, such as his emotion about going back the earth, the eating, shower, brushing, hobbies and his work. Part A and Part B are interviews. So expressing curiosity about the guests’ past life is a communicative skill, which students should be guided to learn.1. Students can get detailed information about how Yang Liwei became an astronaut and Max’s space life.2. Students learn to proper listening strategy to get detailed information---listening for numbers and taking notes.3. Students can learn related sentences or phrases to express their curiosity like “ I wish to know...” “I’d love to know...”4. Students can learn more about the space and astronauts, even be interested in working hard to be an astronaut
新人教版高中英语必修3Unit 4 Space Exploration-Reading and Thinking教学设计二
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?
新人教版高中英语必修3Unit 4 Space Exploration-Reading and Thinking教学设计一
Q4: What is the function of the International exploration ?Having astronauts from different countries on boardQ5: What can you learn from Para 4 ?China has made great achievements in exploring spaceQ6: What is the attitude to the space exploration ?SupportiveStep 6 Post reading---RetellPeople have always wanted to learn more about space. Before the mid-20th century, most people felt (1)_________ (travel) into space was an impossible dream. However, (2)____ the help of scientists, peoplesucceeded in realizing their dream (3) _________ (explore) space. On 4 October 1957, the Sputnik 1 satellite (4) ____________(launch) by the USSR. (5) ________________ scientists try to make sure nothing goes wrong, accidents can still happen. These disasters made everyone(6)___________(disappoint), but people still believe in the importance of (7) ________(carry) on space exploration. In 2003, China became the third country to (8)_____________ (independent) send humans into space. Then Shenzhou 6 and 7 completed (9)____ second manned orbit and the first Chinese spacewalk. In spite of the difficulties, scientists hope future (10)__________ (discovery) will not only enable us to understand the universe but also help us survive well into the future.Answers: 1. travelling 2. with 3. to explore 4. was launched 5. Although6. disappointed 7. carrying 8. independently 9. a 10. discoveriesStep 6 Post reading---Critical thinkingQ1: What do you think of the space exploration ? I think it is beneficial to us. Through further study of space, people will make full use of it in the future, such as the space experiments by Wang Yaping in Tian Gong 1.Q2: If you are determined to be an astronaut, what should you prepare at present ?First of all, I should study hard to get a related college degree. Besides, I must keep mental and physical healthy.Step 7. HomeworkTry to summarize the structure of the article by a mind map.
新人教版高中英语必修3Unit 5 The Value of Money- Discovering Useful Structure教学设计
Step 3 Meaning1. 过去将来时表示从过去某一时间来看将要发生的动作或存在的状态, 常用在宾语从句中。一般由“would/should +动词原形”构成。She hoped that they would meet again someday. 她希望将来有一天他们能再见面。2. was/were going to+动词原形: 表示过去将要发生或很有可能发生的动作, 常用于口语中, 表示预言、意图或者打算等。He was going to start work the following week. 他打算下星期开始工作。3. was/were about to do: 常用来表示即将发生的动作, “刚要/正要做……”。注意该结构不与任何时间状语连用。I felt that something terrible was about to happen. 我感到某种可怕的事情即将发生。4.was/were to do: 表示“曾计划做某事”, 如果表示“本来计划做某事, 动作没实现”, 则需用 “was/were to have done”。She said she was to have told me about the accident. 她说她本来想告诉我关于事故的事。5.Start, go, come, leave, see, meet等动词的过去进行时: 表示就过去某一时刻而言即将发生的动作。She was coming later. 她随后就来。I had just put on my overcoat and was leaving to visit a friend of mine. 我刚穿上外套要去看我的一个朋友。
新人教版高中英语必修3Unit 5 The Value of Money-Listening &Speaking教学设计
Step 4: Listen again and decide if the following statements are true (T) or false (F).1 It was the first time Chen Liyan's story was reported. T口 F口2 Chen found 10,000 yuan in a small plastic bag in Taiyuan railway station口 F口3 Wang Zheng apologized to Chen because he couldn't offer her more money. T口 F口4 Chen took out a large loan to cure her daughter, T口 F口5 Wang set up a fundraising website for Chen's daughter after Chen told him about her situation. T口 F口Step 5：After listening, discuss the questions.1 What kind of person do you think Chen Liyan is?Chen Liyan is generous and honest because she returned a large sum of money to the owner.2 Did Chen return the money because she didn't need it?No. She returned the money because it was the right thing to do. Evidence for this is that she refused to accept the reward money because she felt that it had not been earned. 3 Is it common for people to do what Chen did?It depends on the culture. In some countries it is quite common to return money that has been found. In other countries, people believe "Finders are keepers!" 4 How did Wang Zheng feel about the return of his money?He must have been very happy and relieved to have gotten his money back. We know this because he thanked Chen repeatedly and even offered her a reward.5 Why did Ma Dongbao tell Wang about Chen's family?He must have had great sympathy for Chen and her daughter and wanted to help them.'We know this because he arranged help for them. 6 How did the news reporter feel about Chen's actions?The news reporter felt that it showed that money wasn't the most important thing in life. We know this because the reporter told us that this is what Chen believes. and then said, “that's a great attitude to take."
新人教版高中英语必修3Unit 5 The value of money-Reading and Thinking教学设计二
? 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?
新人教版高中英语必修3Unit 5 The Value of Money-Reading for Writing教学设计二
2. 您能看到, 我头发太长了。You can see that my hair is much too long.3. 无论什么时候, 只要您想回来就回来。Please come back whenever you want.4. 您仅有很少的头发要理! You only have too little hair to cut !5. 为您服务是我的荣幸！It is my honour to serve you!Step 9 Writing(Henry is walking down the street when he sees a sign for a place that cuts hair. He decides to have it cut. )H=Henry B=BarberH: Good afternoon, I’d like to have my hair cut, if I may. (The barber looks at Henry’s hair and continues cutting another man’s hair. ) Er, I’d really like a haircut. As you can see it’s much too long. B: (in a rude manner) Yes, I can see that. Indeed, I can. H: Fine, well, I’ll have a seat then. (He sits in one of the barber’s chairs. The barber turns to look at Henry. )B: It’s quite expensive here, you know! Are you sure you can afford it?H: Yes. I think so. (After his hair is cut, the barber tells Henry how much he must pay. Henry shows the barber the bank note. )B: Why Mr. . . (looks shocked)H: Adams. Henry Adams. I’m sorry. I don’t have any change. B: Please don’t worry! (wearing a big smile) Nothing to worry about! Nothing at all! Please come back whenever you want, even if you only have too little hair to cut! It will be my honour to serve you!Step 10 Pair workExchange drafts with a partner. Use this checklist to help your partner revise his/her draft.1. Are all the elements of a play included and in good order ?2. Do the character use suitable language ?3. Are the stage directions clear and useful ?4. Is the plot clear and exciting enough ?
人教版高中地理必修3第五章第二节产业转移教案
1．阅读图5．16，说明产业向国外转移对日本经济的不利影响。点拨：图5．16直观的显示了产业转移对日本经济的不利影响：形成“产业转移出去的多，转移进来的少→国内生产投资不足，生产困难→市场萎缩→产业向外转移，外资不愿进入”的恶性循环。2．尽管重化工业的环境污染比较严重，但是却能为工业化的发展提供坚实的基础，因此成为发达工业的象征。日本、韩国的经济发展都经历了由轻工业(劳动密集型)到重化工业(资源密集型和资金密集型)到高科技工业(技术密集型)的阶段。(1）为什么日本、韩国在重点发展重化工业之前，要先发展劳动密集型工业?点拨：重化工业的发展一方面需要有一定的工业基础和技术工人，另一方面需要投入大量的资金，先发展劳动密集型工业有利于利用劳动力资源丰富且廉价的优势，积累资金和造就产业工人。所以，劳动力丰富的发展中国家或地区的工业化往往从优先发展劳动密集型工业开始。
人教版高中数学选择性必修二变化率问题教学设计
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。
新人教版高中英语必修3Unit 5 The Value of Money-Discovering Useful Structures导学案
4．They were going to find someone to take part in their bet when they saw Henry walking on the street outside.[归纳]1．过去将来时的基本构成和用法过去将来时由“would＋动词原形”构成，主要表示从过去某一时间来看将要发生的动作(尤其用于宾语从句中)，还可以表示过去的动作习惯或倾向。Jeff knew he would be tired the next day.He promised that he would not open the letter until 2 o'clock.She said that she wouldn't do that again.2．表示过去将来时的其他表达法(1)was/were going to＋动词原形：该结构有两个主要用法，一是表示过去的打算，二是表示在过去看来有迹象表明将要发生某事。I thought it was going to rain.(2)was/were to＋动词原形：主要表示过去按计划或安排要做的事情。She said she was to get married next month.(3)was/were about to＋动词原形：表示在过去看来即将要发生的动作，由于本身已含有“即将”的意味，所以不再与表示具体的将来时间状语连用。I was about to go to bed when the phone rang.(4)was/were＋现在分词：表示在过去看来即将发生的动作，通常可用于该结构中的动词是come，go，leave，arrive，begin，start，stop，close，open，die，join，borrow，buy等瞬间动词。Jack said he was leaving tomorrow.
《一个消逝了的山村》说课稿 2021—2022学年统编版高中语文选择性必修下册
这几段内容传达出的是“要敬畏生命，尊重生命；更要敬畏大自然，尊重大自然，爱护大自然”的主旨内涵，因此让学生通过自由朗读的方式，再次体会冯至对这个消逝了的山村的细致的美好的描绘，感悟冯至传达出的对生命，对自然的理解和思考。5.最后一个自然段的解读依然是交给学生，先齐读课文，再让学生自主分享自己的体会或疑惑。但在这一环节我也设计了两个我认为必须解答的两个问题，一是怎么理解“在风雨如晦的时刻”；二是“意味不尽的关联”是指什么。我认为这两个问题一个涉及到写作背景，一个涉及到对全文主旨的一个整体把握，能够进一步帮助学生理解散文的深刻内涵和主旨，让学生有意识的在阅读散文过程中通过背景知识进行理解。既尊重学生的个性化解读，又能够让学生有意义学习，完成预设的教学目标。如果学生没有提到这两处，那我就需要做出补充。
人教版新课标高中地理必修2第二章第一节城市内部空间结构教案
为城市居民提供休养生息的场所，是城市最基本的功能区．城市中最为广泛的土地利用方式就是住宅用地．一般住宅区占据城市空间的40%—60%。（阅读图2.3）请同学讲解高级住宅区与低级住宅区的差别（学生答）（教师总结）（教师讲解）另外还有行政区、文化区等。而在中小城市，这些部门占地面积很小，或者布局分散，形成不了相应的功能 区。（教师提问）我们把城市功能区分了好几种，比如说住宅区，是不是土地都是被居住地占据呢？是不是就没有其他的功能了呢？（学生回答）不是（教师总结）不是的。我们说的住宅区只是在占地面积上，它是占绝大多数，但还是有土地是被其它功能占据的，比如说住宅区里的商店、绿化等也要占据一定的土地， 只是占的比例比较小而已。下面请看书上的活动题。
人教版新课标高中物理必修1用牛顿运动定律解决问题（二）教案2篇
观察实验视频实验验证师：其实大家完全可以利用身边的器材来验证。实验1、用弹簧秤挂上钩码，然后迅速上提和迅速下放。现象：在钩码被迅速上提的一瞬间，弹簧秤读数突然变大；在钩码被迅速下放的一瞬间，弹簧秤读数突然变小。师：迅速上提时弹簧秤示数变大是超重还是失重？迅速下放时弹簧秤示数变小是超重还是失重？生：迅速上提超重，迅速下放失重。体会为何用弹簧秤测物体重力时要保证在竖直方向且保持静止或匀速实验2、学生站在医用体重计上，观察下蹲和站起时秤的示数如何变化？在实验前先让同学们理论思考示数会如何变化再去验证，最后再思考。（1）在上升过程中可分为两个阶段：加速上升、减速上升；下蹲过程中也可分为两个阶段：加速下降、减速下降。（2）当学生加速上升和减速下降时会出现超重现象；当学生加速下降和减速上升时会出现失重现象；（3）出现超重现象时加速度方向向上，出现失重现象时加速度方向向下。完全失重
人教版新课标高中物理必修1用牛顿运动定律解决问题（一）教案2篇
（四）实例探究☆力和运动的关系1、一个物体放在光滑水平面上，初速为零，先对物体施加一向东的恒力F，历时1秒，随即把此力改变为向西，大小不变，历时1秒钟，接着又把此力改为向东，大小不变，历时1秒钟，如此反复只改变力的方向，共历时1分钟，在此1分钟内A．物体时而向东运动，时而向西运动，在1分钟末静止于初始位置之东B．物体时而向东运动，时而向西运动，在1分钟末静止于初始位置C．物体时而向东运动，时而向西运动，在1分钟末继续向东运动D．物体一直向东运动，从不向西运动，在1分钟末静止于初始位置之东☆牛顿运动定律的应用2、用30N的水平外力F，拉一静止放在光滑的水平面上质量为20kg的物体，力F作用3秒后消失，则第5秒末物体的速度和加速度分别是A．v=7.5m／s，a=l.5m／s2B．v=4.5m／s，a=l.5m／s2C．v=4.5m／s，a=0D．v=7.5m／s，a=0
高中物理必修1教案高中物理必修二圆周运动教案
一、描述圆周运动的物理量 探究交流 打篮球的同学可能玩过转篮球，让篮球在指尖旋转，展示自己的球技，如图5-4-1所示.若篮球正绕指尖所在的竖直轴旋转，那么篮球上不同高度的各点的角速度相同吗?线速度相同吗? 【提示】 篮球上各点的角速度是相同的.但由于不同高度的各点转动时的圆心、半径不同，由v=ωr可知不同高度的各点的线速度不同.
用空间向量研究直线、平面的位置关系（2）教学设计人教A版高中数学选择性必修第一册
跟踪训练1在正方体ABCD-A1B1C1D1中,E为AC的中点.求证:(1)BD1⊥AC;(2)BD1⊥EB1.(2)∵(BD_1 ) ?=(-1,-1,1),(EB_1 ) ?=(1/2 "," 1/2 "," 1),∴(BD_1 ) ?·(EB_1 ) ?=(-1)×1/2+(-1)×1/2+1×1=0,∴(BD_1 ) ?⊥(EB_1 ) ?,∴BD1⊥EB1.证明:以D为原点,DA,DC,DD1所在直线分别为x轴、y轴、z轴,建立如图所示的空间直角坐标系.设正方体的棱长为1,则B(1,1,0),D1(0,0,1),A(1,0,0),C(0,1,0),E(1/2 "," 1/2 "," 0),B1(1,1,1).(1)∵(BD_1 ) ?=(-1,-1,1),(AC) ?=(-1,1,0),∴(BD_1 ) ?·(AC) ?=(-1)×(-1)+(-1)×1+1×0=0.∴(BD_1 ) ?⊥(AC) ?,∴BD1⊥AC.例2在棱长为1的正方体ABCD-A1B1C1D1中,E,F,M分别为棱AB,BC,B1B的中点.求证:D1M⊥平面EFB1.思路分析一种思路是不建系,利用基向量法证明(D_1 M) ?与平面EFB1内的两个不共线向量都垂直,从而根据线面垂直的判定定理证得结论;另一种思路是建立空间直角坐标系,通过坐标运算证明(D_1 M) ?与平面EFB1内的两个不共线向量都垂直;还可以在建系的前提下,求得平面EFB1的法向量,然后说明(D_1 M) ?与法向量共线,从而证得结论.证明:(方法1)因为E,F,M分别为棱AB,BC,B1B的中点,所以(D_1 M) ?=(D_1 B_1 ) ?+(B_1 M) ?=(DA) ?+(DC) ?+1/2 (B_1 B) ?,而(B_1 E) ?=(B_1 B) ?+(BE) ?=(B_1 B) ?-1/2 (DC) ?,于是(D_1 M) ?·(B_1 E) ?=((DA) ?+(DC) ?+1/2 (B_1 B) ?)·((B_1 B) ?-1/2 (DC) ?)=0-0+0-1/2+1/2-1/4×0=0,因此(D_1 M) ?⊥(B_1 E) ?.同理(D_1 M) ?⊥(B_1 F) ?,又因为(B_1 E) ?,(B_1 F) ?不共线,因此D1M⊥平面EFB1.