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新人教版高中英语必修3Unit 1 Festivals and Celebrations-Listening &Speaking＆Talking教学设计
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.
新人教版高中英语必修3Unit 1 Festivals and Celebrations-Reading for writing教学设计二
Step 3 Analyzing article structureActivity 31. Teachers raise questions to guide students to analyze the chapter structure of this diary and think about how to describe the festival experience. (1)What should be included in the opening/body/closing paragraph(s)?(2)How did the writer arrange his/her ideas?(3)What kind of interesting details did the writer describe?(4)How did the writer describe his/her feelings/emotions during the event?2. Students read and compare the three sentence patterns in activity 2. Try to rewrite the first paragraph of the diary with these three sentence patterns. After that, students exchange corrections with their partners. Such as:●This was my first time spending three days experiencing the Naadam Festival in China’s Inner Mongolia Autonomous Region and it was an enjoyable and exciting experience. ●I'll never forget my experience at the Naadam Festival because it was my first time to watch the exciting Mongolian games of horse racing, wrestling, and archery so closely. ●I'll always remember my first experience at the Naadam Festival in China’s Inner Mongolia Autonomous Region because it was so amazing to spend three days witnessing a grand Mongolian ceremony. Step 4 Accumulation of statementsActivity 41. Ask the students to read the diary again. Look for sentences that express feelings and emotions, especially those with the -ing form and the past participle. Such as:● …horse racing, wrestling, and archery, which are all so exciting to watch. ● some amazing performances● I was surprised to see…● I was a little worried about. . . ● feeling really tiredOther emotional statements:●I absolutely enjoyed the archery, too, but the horse races were my favourite part. ●I'm finally back home now, feeling really tired, but celebrating Naadam with my friend was totally worth it. ●He invited me back for the winter to stay in a traditional Mongolian tent and cat hot pot. I can’t wait!2. In addition to the use of the -ing form and the past participle, the teacher should guide the students in the appreciation of these statements, ask them to memorize them, and encourage them to use them reasonably in writing practice.
新人教版高中英语必修3Unit 1 Festivals and Celebrations-Reading for Writing教学设计一
The topic of this part is “Write about your festival experience”.During the Listening and Speaking and Talking, students are just asked to say out their festival experiences such as the Spring Festival, Mid-autumn Day, but this part students will be asked to write down their own festival experiences. During the reading part, it introduces the Naadam Festival in Inner Mongolia Autonomous Region, which can give students a good example to imitate. Students not only learn the festival, but touch and feel the Inner Mongolian’s character, the spirit and cultural atmosphere, which can help students form the cultural awareness and learn to enjoy and value the diversity of Chinese culture.Concretely, the dairy tells the experience that the author spent the Naadam Festival in Inner Mongolia Autonomous Region with his/her friend. The structure is clear. In the opening paragraph, it introduces the topic of the Naadam Festival and the whole feeling. Then it introduces the items of the festival like the ceremony, wrestling and horse racing. Finally, it summarizes this experience. Because this part is a travel journal, we must guide students pay more attention to these details: 1. use the first person. 2. use the past tense to tell the past thing and use the present or future tense to describe the scenery. 3. use the timeline to tell the development. 4. be careful for the author’s psychology, emotion and feeling, etc.1. Read quickly to get main idea; read carefully to get the detailed information about Naadam Festival.2. Learn the structure of the reading article and language.3. Write an article about a festival experience4. Learn to use the psychology, emotions and feeling in the writing.1. Write an article about a festival experience.2. Use the structure of the reading article and language.
新人教版高中英语选修2Unit 1 Science and Scientists-Discovering useful structures教学设计
The grammatical structure of this unit is predicative clause. Like object clause and subject clause, predicative clause is one of Nominal Clauses. The leading words of predicative clauses are that, what, how, what, where, as if, because, etc.The design of teaching activities aims to guide students to perceive the structural features of predicative clauses and think about their ideographic functions. Beyond that, students should be guided to use this grammar in the context apporpriately and flexibly.1. Enable the Ss to master the usage of the predicative clauses in this unit.2. Enable the Ss to use the predicative patterns flexibly.3. Train the Ss to apply some skills by doing the relevant exercises.1.Guide students to perceive the structural features of predicative clauses and think about their ideographic functions.2.Strengthen students' ability of using predicative clauses in context, but also cultivate their ability of text analysis and logical reasoning competence.Step1: Underline all the examples in the reading passage, where noun clauses are used as the predicative. Then state their meaning and functions.1) One theory was that bad air caused the disease.2) Another theory was that cholera was caused by an infection from germs in food or water.3) The truth was that the water from the Broad Street had been infected by waste.Sum up the rules of grammar:1. 以上黑体部分在句中作表语。2. 句1、2、3中的that在从句中不作成分，只起连接作用。 Step2: Review the basic components of predicative clauses1.Definition
新人教版高中英语选修2Unit 1 Science and Scientists-Learning about Language教学设计
Step 7: complete the discourse according to the grammar rules.Cholera used to be one of the most 1.__________ (fear) diseases in the world. In the early 19th century, _2_________ an outbreak of cholera hit Europe, millions of people died. But neither its cause, 3__________ its cure was understood. A British doctor, John Snow, wanted to solve the problem and he knew that cholera would not be controlled _4_________ its cause was found. In general, there were two contradictory theories 5 __________ explained how cholera spread. The first suggested that bad air caused the disease. The second was that cholera was caused by an _6_________(infect) from germs in food or water. John Snow thought that the second theory was correct but he needed proof. So when another outbreak of cholera hit London in 1854, he began to investigate. Later, with all the evidence he _7_________ (gather), John Snow was able to announce that the pump water carried cholera germs. Therefore, he had the handle of the pump _8_________ (remove) so that it couldn't be used. Through his intervention，the disease was stopped in its tracks. What is more, John Snow found that some companies sold water from the River Thames that __9__________________ (pollute) by raw waste. The people who drank this water were much more likely _10_________ (get) cholera than those who drank pure or boiled water. Through John Snow's efforts, the _11_________ (threaten) of cholera around the world saw a substantial increase. Keys： 1.feared 2.when 3. nor 4.unless 5.that/which 6.infection 7.had gathered 8.removed 9.was polluted 10.to get 11. threat
新人教版高中英语选修2Unit 1 Science and Scientists-Reading and thinking教学设计
Step 5： After learning the text, discuss with your peers about the following questions:1.John Snow believed Idea 2 was right. How did he finally prove it?2. Do you think John Snow would have solved this problem without the map?3. Cholera is a 19th century disease. What disease do you think is similar to cholera today?SARS and Covid-19 because they are both deadly and fatally infectious, have an unknown cause and need serious public health care to solve them urgently.keys:1. John Snow finally proved his idea because he found an outbreak that was clearly related to cholera, collected information and was able to tie cases outside the area to the polluted water.2. No. The map helped John Snow organize his ideas. He was able to identify those households that had had many deaths and check their water-drinking habits. He identified those houses that had had no deaths and surveyed their drinking habits. The evidence clearly pointed to the polluted water being the cause.3. SARS and Covid-19 because they are both deadly and fatally infectious, have an unknown cause and need serious public health care to solve them urgently.Step 6: Consolidate what you have learned by filling in the blanks:John Snow was a well-known _1___ in London in the _2__ century. He wanted to find the _3_____ of cholera in order to help people ___4_____ it. In 1854 when a cholera __5__ London, he began to gather information. He ___6__ on a map ___7___ all the dead people had lived and he found that many people who had ___8____ (drink) the dirty water from the __9____ died. So he decided that the polluted water ___10____ cholera. He suggested that the ___11__ of all water supplies should be _12______ and new methods of dealing with ____13___ water be found. Finally, “King Cholera” was __14_____.Keys: 1. doctor 2. 19th 3.cause 4.infected with 5.hit 6.marked 7.where 8.drunk 9.pump 10.carried 11.source 12.examined 13.polluted 14.defeatedHomework: Retell the text after class and preview its language points
新人教版高中英语选修2Unit 1 Science and Scientists-Using langauge教学设计
This happens because the dish soap molecules have a strong negative charge, and the milk molecules have a strong positive charge. Like magnets, these molecules are attracted to each other, and so they appear to move around on the plate, taking the food coloring with them, making it look like the colors are quickly moving to escape from the soap.Listening text:? Judy: Oh, I'm so sorry that you were ill and couldn't come with us on our field trip. How are you feeling now? Better?? Bill: Much better, thanks. But how was it?? Judy: Wonderful! I especially liked an area of the museum called Light Games.it was really cool. They had a hall of mirrors where I could see myself reflected thousands of times!? Bill: A hall of mirrors can be a lot of fun. What else did they have?? Judy: Well, they had an experiment where we looked at a blue screen for a while, and then suddenly we could see tiny bright lights moving around on it. You'll never guess what those bright lights were!? Bill: Come on, tell me!? Judy: They were our own blood cells. For some reason, our eyes play tricks on us when we look at a blue screen, and we can see our own blood cells moving around like little lights! But there was another thing I liked better. I stood in front of a white light, and it cast different shadows of me in every color of the rainbow!? Bill: Oh, I wish I had been there. Tell me more!? Judy: Well, they had another area for sound. They had a giant piano keyboard that you could use your feet to play. But then, instead of playing the sounds of a piano, it played the voices of classical singers! Then they had a giant dish, and when you spoke into it, it reflected the sound back and made it louder. You could use it to speak in a whisper to someone 17 meters away.? Bill: It all sounds so cool. I wish I could have gone with you? Judy: I know, but we can go together this weekend. I'd love to go there again!? Bill: That sounds like a great idea!
大班科学教案：旋转的彩球（科学）
2．幼儿操作材料：长铜丝、短铜丝若干，粗细不同的圆铅笔、吸管、小棒等若干，圆形彩纸片若干，浆糊、抹布，橡皮泥，别针。活动内容：1．演示彩球玩具，引起幼儿兴趣。⑴教师演示玩具，请幼儿观察现象。⑵介绍玩具的构造。①教师：这个玩具有几个部分组成的呢？②示范弹簧的制作方法。2．请幼儿来制作玩具。⑴幼儿尝试自己制作旋转彩球玩具，教师巡回指导。⑵幼儿玩一玩自己制作的玩具。⑶交流制作经验。教师：①你是怎样做旋转彩球的？你的彩球能滑下来吗？怎样滑下来的？②师生共同小结。3．讨论：为什么彩球下滑转动快慢不一样。⑴比一比：谁的小球转得快？⑵想一想：为什么彩球转的快慢不一样呢？弹簧粗的转得快还是弹簧细的转得快？⑶小结：原来有的小朋友他绕的弹簧比较细，所以彩球转的快；有的小朋友绕的弹簧粗，所以彩球转的慢些。4．怎样使彩球转得快些。⑴猜一猜：不改变弹簧的粗细能不能让彩球转得快些？⑵幼儿尝试，教师做必要的提醒和指导。⑶小结：活动延伸：1．将材料投放在科学角，供幼儿平时操作。提供橡皮泥，鼓励幼儿尝试将纸球换成橡皮泥，改变两边橡皮泥的重量，观察其下滑速度的变化。2．在日常生活中引导幼儿观察重力与速度变化的现象。活动建议：1．长短铜丝应分别为两种规格，利于幼儿对比。
大班科学教案：科学幻想故事
过程 活动（一）欣赏科幻故事 1、由教师讲科幻故事。如“机器人奇奇”、“我的梦”、“到月球上去”、“海底旅游”等。 2、组织幼儿观看科幻录像片。如“机器猫”、“可赛号”、“变形金刚”等。 3、让幼儿自由阅读关于科学知识或幻想故事的图书。 活动（二）创编科幻故事 1、续编故事：让幼儿根据自己知道的科幻故事中的人物、背景、情节继续编故事。
大班科学教案：化学游戏：找动物
活动目标： 1．运用化学小魔术，充分激发幼儿的探究兴趣和积极尝试的欲望。 2．通过游戏活动，使幼儿了解酚酞溶液遇到另一种药水（稀碱溶液）会变成红色的现象，真切地感受到大自然的奇妙。 活动准备： 1．稀碱溶液、酚酞溶液、清水。 2．毛笔、杯子、双面胶； 3．水彩纸数张，教师示范画一张（事先均用彩笔画好树林、房屋等，用毛笔蘸取稀碱溶液画狐狸、老虎、大灰狼隐藏在树林中，晾干），白纸数张（事先用稀碱溶液画上小动物，晾干）。 活动过程： 一、教师做化学小魔术，激发幼儿兴趣。 1．教师出示一张已用稀碱画了小动物的白纸，问：“纸上有什么？”“有小动物隐身在白纸里，可以用什么办法把它请出来？”（幼儿自由畅想）。 2．教师演示： 提问：“老师用什么方法把毛毛虫请了出来？” 3．引导幼儿对水和酚酞进行比较（用试一试、看一看、闻一闻的方法） 教师小结：刚才老师请毛毛虫用的不是水，而是一杯神奇的药水，它的名字叫酚酞。
大班科学教案：冻冰花（科学、艺术）
2.引导幼儿感受冬天气温的变化，探索水的形态变化与气温的关系。 3.引导幼儿学习动手制作冰花、欣赏冰花，培养幼儿的审美能力。活动准备： 1.矿泉水瓶、清水、细绳、花瓣、树叶、小石头等。 2.温度计若干。活动过程： 1.在天气不是很冷的时候布置幼儿回家制作冰花后，请带来冰花的幼儿讲讲怎样做的冰花，请没带冰花的幼儿讲讲为什么没带。让幼儿知道天气不太冷的时候室外是冻不出冰花的。 “你的冰花在哪里做成的？”（冰箱里） “你为什么不放在院子里或房间里冻冰花”？ “为什么院子里、房间里冻不成冰花”？
空间向量及其运算的坐标表示教学设计人教A版高中数学选择性必修第一册
一、情境导学我国著名数学家吴文俊先生在《数学教育现代化问题》中指出:“数学研究数量关系与空间形式,简单讲就是形与数,欧几里得几何体系的特点是排除了数量关系,对于研究空间形式,你要真正的‘腾飞’,不通过数量关系,我想不出有什么好的办法…….”吴文俊先生明确地指出中学几何的“腾飞”是“数量化”,也就是坐标系的引入,使得几何问题“代数化”,为了使得空间几何“代数化”,我们引入了坐标及其运算.二、探究新知一、空间直角坐标系与坐标表示1.空间直角坐标系在空间选定一点O和一个单位正交基底{i,j,k},以点O为原点,分别以i,j,k的方向为正方向、以它们的长为单位长度建立三条数轴:x轴、y轴、z轴,它们都叫做坐标轴.这时我们就建立了一个空间直角坐标系Oxyz,O叫做原点,i,j,k都叫做坐标向量,通过每两个坐标轴的平面叫做坐标平面,分别称为Oxy平面,Oyz平面,Ozx平面.
抛物线的简单几何性质（2）教学设计人教A版高中数学选择性必修第一册
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，
抛物线及其标准方程教学设计人教A版高中数学选择性必修第一册
本节课选自《2019人教A版高中数学选择性必修第一册》第二章《直线和圆的方程》，本节课主要学习抛物线及其标准方程在经历了椭圆和双曲线的学习后再学习抛物线，是在学生原有认知的基础上从几何与代数两 个角度去认识抛物线.教材在抛物线的定义这个内容的安排上是：先从直观上认识抛物线，再从画法中提炼出抛物线的几何特征，由此抽象概括出抛物线的定义，最后是抛物线定义的简单应用.这样的安排不仅体现出《课程标准》中要求通过丰富的实例展开教学的理念，而且符合学生从具体到抽象的认知规律，有利于学生对概念的学习和理解.坐标法的教学贯穿了整个“圆锥曲线方程”一章，是学生应重点掌握的基本数学方法 运动变化和对立统一的思想观点在这节知识中得到了突出体现，我们必须充分利用好这部分教材进行教学
双曲线的简单几何性质（2）教学设计人教A版高中数学选择性必修第一册
二、典例解析例4．如图，双曲线型冷却塔的外形，是双曲线的一部分，已知塔的总高度为137.5m，塔顶直径为90m，塔的最小直径(喉部直径)为60m，喉部标高112.5m，试建立适当的坐标系，求出此双曲线的标准方程（精确到1m）解:设双曲线的标准方程为 ，如图所示：为喉部直径，故 ，故双曲线方程为 .而 的横坐标为塔顶直径的一半即 ，其纵坐标为塔的总高度与喉部标高的差即 ，故 ，故 ，所以 ，故双曲线方程为 .例5．已知点 到定点 的距离和它到定直线l: 的距离的比是 ，则点 的轨迹方程为?解：设点 ，由题知, ，即 .整理得： .请你将例5与椭圆一节中的例6比较，你有什么发现？例6、 过双曲线 的右焦点F2,倾斜角为30度的直线交双曲线于A,B两点,求|AB|.分析:求弦长问题有两种方法:法一:如果交点坐标易求,可直接用两点间距离公式代入求弦长;法二:但有时为了简化计算,常设而不求,运用韦达定理来处理.解：由双曲线的方程得，两焦点分别为F1(-3,0),F2(3,0).因为直线AB的倾斜角是30°，且直线经过右焦点F2，所以，直线AB的方程为
双曲线及其标准方程教学设计人教A版高中数学选择性必修第一册
∵在△EFP中,|EF|=2c,EF上的高为点P的纵坐标,∴S△EFP=4/3c2=12,∴c=3,即P点坐标为(5,4).由两点间的距离公式|PE|=√("(" 5+3")" ^2+4^2 )=4√5,|PF|=√("(" 5"-" 3")" ^2+4^2 )=2√5,∴a=√5.又b2=c2-a2=4,故所求双曲线的方程为x^2/5-y^2/4=1.5.求适合下列条件的双曲线的标准方程.(1)两个焦点的坐标分别是(-5,0),(5,0),双曲线上的点与两焦点的距离之差的绝对值等于8;(2)以椭圆x^2/8+y^2/5=1长轴的端点为焦点,且经过点(3,√10);(3)a=b,经过点(3,-1).解:(1)由双曲线的定义知,2a=8,所以a=4,又知焦点在x轴上,且c=5,所以b2=c2-a2=25-16=9,所以双曲线的标准方程为x^2/16-y^2/9=1.(2)由题意得,双曲线的焦点在x轴上,且c=2√2.设双曲线的标准方程为x^2/a^2 -y^2/b^2 =1(a>0,b>0),则有a2+b2=c2=8,9/a^2 -10/b^2 =1,解得a2=3,b2=5.故所求双曲线的标准方程为x^2/3-y^2/5=1.(3)当焦点在x轴上时,可设双曲线方程为x2-y2=a2,将点(3,-1)代入,得32-(-1)2=a2,所以a2=b2=8.因此,所求的双曲线的标准方程为x^2/8-y^2/8=1.当焦点在y轴上时,可设双曲线方程为y2-x2=a2,将点(3,-1)代入,得(-1)2-32=a2,a2=-8,不可能,所以焦点不可能在y轴上.综上,所求双曲线的标准方程为x^2/8-y^2/8=1.
椭圆的简单几何性质（2）教学设计人教A版高中数学选择性必修第一册
二、典例解析例5. 如图，一种电影放映灯的反射镜面是旋转椭圆面（椭圆绕其对称轴旋转一周形成的曲面）的一部分。过对称轴的截口 ABC是椭圆的一部分，灯丝位于椭圆的一个焦点F_1上，片门位另一个焦点F_2上，由椭圆一个焦点F_1 发出的光线，经过旋转椭圆面反射后集中到另一个椭圆焦点F_2，已知 〖BC⊥F_1 F〗_2，|F_1 B|=2.8cm, |F_1 F_2 |=4.5cm,试建立适当的平面直角坐标系，求截口ABC所在的椭圆方程(精确到0.1cm)典例解析解：建立如图所示的平面直角坐标系，设所求椭圆方程为x^2/a^2 +y^2/b^2 =1 (a>b>0) 在Rt ΔBF_1 F_2中,|F_2 B|= √(|F_1 B|^2+|F_1 F_2 |^2 )=√(〖2.8〗^2 〖+4.5〗^2 ) 有椭圆的性质 , |F_1 B|+|F_2 B|=2 a, 所以a=1/2(|F_1 B|+|F_2 B|)=1/2(2.8+√(〖2.8〗^2 〖+4.5〗^2 )) ≈4.1b= √(a^2 〖-c〗^2 ) ≈3.4所以所求椭圆方程为x^2/〖4.1〗^2 +y^2/〖3.4〗^2 =1 利用椭圆的几何性质求标准方程的思路1．利用椭圆的几何性质求椭圆的标准方程时，通常采用待定系数法，其步骤是：(1)确定焦点位置；(2)设出相应椭圆的标准方程(对于焦点位置不确定的椭圆可能有两种标准方程)；(3)根据已知条件构造关于参数的关系式，利用方程(组)求参数，列方程(组)时常用的关系式有b2＝a2－c2等．
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.
人教版新课标PEP小学英语三年级下册Do you like pears说课稿9篇
第一环节：教师参与到其中的一个小组，用“Do you like…？”的句型提问，因为学生在上学期已经接触了“like”一词，现在又有了前面三次听的机会，对本课所要学的对话有了一定的感知，预计有部分学生会回答“Yes，Ido.或No，I don’t .”当学生回答“Yes，Ido.”时，我就说：“Here you are .”同时也将水果递给学生。在教师与学生、学生与学生的对话中，领悟了“Yes，Ido.”和“Here you are .”的意思。当学生回答“No, I don’t.” 时，教师不把水果递给他。通过这个过程的口语与演示，学生也会领悟到“No, I don’t.”的意思。同时，进行师问生答的口语操练。师生对话要适当增加，使学生对“Yes，Ido.和No, I don’t”的句型有更多的操练机会。这样，第一环节的目标也就达到了。第二环节：由师问生答的形式，变为生问师答。通过教师引导，让学生用“Do you like …”提问。因为，学生要把“Do you like …”的音读准，有一定难度。因此，在起先学生说这句式时，要发挥教师的主导作用，让学生跟读，注重学生发音的准确。
人教版新课标PEP小学英语三年级下册How many说课稿7篇
我随意走动，观察学生们用英语交流的情况，有困难的适时指导一下。学生们在完成任务的过程中，积极运用语言，激发了学习兴趣，同时还实现了与数学学科的渗透和联系。在这节课的最后，我布置了一个有层次的作业，让学生自主选择：①听录音，仿读会话；②分角色表演会话；③改编会话，分角色表演并录成磁带。分层次的作业，让不同程度的学生都能有事可做，都有表现自己的机会，体验到成功的喜悦，同时使学生的语言交际向课外延伸，使他们能带着动力，保持兴趣继续学习。总之，在这节课的教学设计中，我重视对新知识的铺垫和自然导入，通过多种方式的呈现，让学生们自然而然地学习新知识。充分利用游戏、合作交流等教学手段，让学生们饶有兴趣地操练语言、运用语言，在完成任务过程中巩固知识，运用知识，体验成功的喜悦，培育积极的学习情感，形成良好的学习策略，并将这些积极的因素带人下一步的学习当中。
