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人教版高中语文必修5《边城》教案

  • 新人教版高中英语必修1Unit 2 Travelling Around-Reading and Thinking教案

    新人教版高中英语必修1Unit 2 Travelling Around-Reading and Thinking教案

    Good expressions that students can choose to use: help the travelers choose which tour to take1. In my opinion, you could/might choose…, because you prefer to…2. …could be a perfect choice for you, for…3. As far as I am concerned, you would enjoy…, for…4. …would probably suit you, because you enjoy/love/hate doing…Step 5 Passage ConsolidationLanguage appreciation:1. You can then spend three days exploring the rainforest with a local guide and enjoying the plants and animals unique to the rainforest. 在接下来的三天里,您可以在当地导游的陪同下,深入雨林进行探索,欣赏雨林特有的动植物。本句主体结构为spend some time doing sth. 2. Inca builders cut stones to exact sizes so that nothing was needed to hold walls together other than the perfect fit of the stones. 印加的建筑工人将石头切割成精确的尺寸,仅仅凭着石头间的完美契合,即可稳固墙体。本句为so that引导的结果状语从句。nothing与the perfect fit为并列成分; other than在句中意为“除了”。Step 6 HomeworkSuppose you will travel to Peru, write a short essay about your three-day tour plan.

  • 新人教版高中英语必修1Unit 3 Sports and Fitness-Reading for Writing教案

    新人教版高中英语必修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.健康书的审题步骤:第一步:明确要求该写作属于经验分享,故要用第一人称来写;时态以一股现在时为主。第二步:确定段落该类文章可以从以下三个方面人手:Para.1首先表明写作的目的Para.2自己的做法及心得体会Para.3表示期望及感谢第三步:提炼要点2.健康书常见句式: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假如你的老师让你在班级Wellness Bok上分享自己的亲身经历及心得,请根据以下要点写一篇80字左右的文章1. 你喜欢的运动是什么?2. 你最喜欢的原因是什么?3. 你参加锻炼的体会。

  • 新人教版高中英语必修1Unit 4 Natural Disasters- Reading for writing教案

    新人教版高中英语必修1Unit 4 Natural Disasters- Reading for writing教案

    ①标题——标题应当简洁明了。②导语——导语是消息开头的第一段或第一句话,简明扼要地揭示出消息的核心内容。③主体——主体是消息的主要部分,要用充足的事实表现主题,对导语的内容作进一步的展开和阐述。④结束语——通常是对全文内容进行概括性的总结。3. 新闻报道增分句子(1)陈述事实常用的句型: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.地震发生在一个凉爽的秋夜。大量的建筑物倒塌,道路被毁,许多人无家可归。③With the help of the rescue team, people who were the trapped in the flood were saved.在救援队的帮助下,困在洪水中的人们得救了。(2)陈述观点常用的句型:①Clearly/Obviously/In my opinion/It seemed that people were shocked.显然/在我看来/似乎人们震惊了。②The whole city was in ruins after the earthquake.地震后整个城市成了一片废墟。(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.

  • 新人教版高中英语必修1Unit 4 Natural Disasters-Discovering Useful Structures教案

    新人教版高中英语必修1Unit 4 Natural Disasters-Discovering Useful Structures教案

    【教材分析】This teaching period mainly deals with the grammar: the restrictive relative clauses.This period carries considerable significance to the cultivation of students’ writing competence and lays a solid foundation for the basic appreciation of language beauty. The teacher is expected to enable students to master this period thoroughly and consolidate the knowledge by doing some exercise of good quality.【教学目标与核心素养】1. Get students to have a good understanding of the basic usages of the restrictive relative clauses.2. Enable students to use the restrictive relative clauses flexibly.3. Develop students’ speaking and cooperating abilities.4. Strengthen students’ great interest in grammar learning.【教学重难点】How to enable students to have a good understanding of the restrictive relative clauses, especially the uses of the relative words such as which, that, who, whom.【教学过程】Step1: 语法知识呈现定语从句(一)—关系代词的用法在复合句中, 修饰名词或代词的从句叫定语从句。定语从句通常由关系代词或关系副词引导,说明事物的具体信息,从句位于被修饰词之后。被定语从句修饰的词叫先行词,引导定语从句的词叫关系词,关系词指代先行词,并在定语从句中充当成分。关系词有两种:关系代词who, whom ,whose, that, which, as和关系副词when, where, why。

  • 新人教版高中英语必修1Welcome Unit-Discovering Useful Structures & Listening and Talking教案

    新人教版高中英语必修1Welcome Unit-Discovering Useful Structures & Listening and Talking教案

    常跟双宾语的动词有:(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+谓+宾+宾补)特点:动词虽然是及物动词,但是只跟一个宾语还不能表达完整的意思,必须加上一个补充成分来补足宾语,才能使意思完整。 判断原则:能表达成—宾语 是…/做…注:此结构由“主语+及物的谓语动词+宾语+宾语补足语”构成。宾语与宾语补足语之间有逻辑上的主谓关系或主表关系,若无宾语补足语,则句意不够完整。可以用做宾补的有:名词,形容词,副词,介词短语,动词不定式,分词等。如:He considers himself an expert on the subject.他认为自己是这门学科的专家。We must keep our classroom clean.我们必须保持教室清洁。I had my bike stolen.我的自行车被偷了。We invited him to come to our school.我们邀请他来我们学校。I beg you to keep secret what we talked here.我求你对这里所谈的话保密。用it做形式宾语,而将真正的宾语放到宾语补足语的后面,以使句子结构平衡,是英语常用的句型结构方式。即:主语+谓语+it+宾补+真正宾语。如:We think it a good idea to go climb the mountain this Sunday.

  • 新人教版高中英语必修2Unit 1 Cultural Heritage-Discovering Useful Structure教案一

    新人教版高中英语必修2Unit 1 Cultural Heritage-Discovering Useful Structure教案一

    This teaching period mainly deals with grammar “restrictive relative clauses.” To begin with, teachers should lead students to revise what they have learned about the relative pronouns and relative adverbs. And then, teachers move on to stress more special cases concerning this grammar, such as the “preposition+ relative pronouns which and whom” and cases where we can omit the relative pronouns. This period carries considerable significance to the cultivation of students’ writing competence and lays a solid foundation for the basic appreciation of language beauty. The teacher is expected to enable students to master this period thoroughly and consolidate the knowledge by doing some exercises. 1. Guide students to review the basic usages of relative pronouns and adverbs of attributive clauses.2. Lead students to learn to use some special cases concerning restrictive relative clauses flexibly.2. Enable students to use the basic phrases structures flexibly.3. Strengthen students’ great interest in grammar learning.1. Help students to appreciate the function of relative pronouns and adverbs of attributive clauses in a sentence2. Instruct students to write essays using the proper relative pronouns and adverbs of attributive clauses.本节语法思考:定语从句在复合句中的作用是什么? 关系词有哪些?定语从句在复合句中的作用相当于形容词,它在句中作定语修饰名词或代词。他们在先行词和定语从句之间起到联系作用,同时在意义上代表先行词并在定语从句中担任一个成分。被定语从句所修饰的词称先行词,定语从句一般放在先行词的后面。

  • 新人教版高中英语必修2Unit 1 Cultural Heritage-Reading and Thinking教案一

    新人教版高中英语必修2Unit 1 Cultural Heritage-Reading and Thinking教案一

    The theme of the reading and thinking is about “Understanding how a problem was solved”.The Listening & Speaking & Talking is about international co-work to protect the Mount Tai, in which the students from seven countries came up with many solutions even create the Mount Tai App. This section aims at showing how to solve a difficult and even tough problem about protecting the cultural heritage by the international co-work. So in this section, cultivating students’ international awareness is very clear and important. Concretely, with the economic development, how to balance the protection of cultural relics and social development is a big challenge for human. In the 1950s, the Egyptian government wanted to build the Aswan Dam across the Nile to control floods, produce electricity and water farms. But the proposal led to protests because it would destroy a lot of cultural relics. The Egyptian had no choice but ask the UN for help. Therefore, a international cooperation about how to protect the cultural relics began, which involved the time length about 20 years and a large amount of fund. Then, the problems was solved. 1. Read quickly to get the main idea and the structure of the article; read careful to get detailed information.2. Learn to use the reading strategy---making a timeline3. Learn how to solve a tough problem by asking for help and cooperation4. Have the international awareness and understand the great strength of international cooperation.1. Read quickly to get the main idea and the structure of the article; read careful to get detailed information.2. Learn to use the reading strategy---making a timeline.3. Learn how to solve a tough problem by asking for help and cooperation.

  • 新人教版高中英语必修2Unit 2 Wildlife Protection-Discovering Useful Structure教案一

    新人教版高中英语必修2Unit 2 Wildlife Protection-Discovering Useful Structure教案一

    The activity topic of this section is "report an ongoing event", and the structure is the passive voice of present continuous tense. Rare wild animals are suffering from large-scale poaching, and species are on the brink of danger. Rescue operations are underway. "Being" and "suffering" are the meanings of the present progressive passive voice.The usage of present progressive passive voice is of great importance in writing a good discourse and appreciating some difficult language items, so it is vital to master it and use it flexibly in a context.1. Motivate Ss to deepen the understanding of the usage of present progressive passive voice in a fixed context.2. Enable Ss to master the usage of present progressive passive voice and use it flexibly in a context.3. Lead Ss to construct sentences or appreciate sentences used master it and use it flexibly in a context.1. Help students to appreciate the function of the usage of present progressive passive voice in a sentence2. Instruct students to write essays using the proper usage of present progressive passive voice.Look at the picture and tell me what are workers doing? What is the house being done?

  • 新人教版高中英语必修2Unit 2 Wildlife Protection-Listening and Speaking教案

    新人教版高中英语必修2Unit 2 Wildlife Protection-Listening and Speaking教案

    This lesson is about wildlife protection. The listening and speaking is about “How to protect endangered wildlife ?” Faced with the facts and numbers of wildlife loss, people begin to detect the reasons, then people such as the celebrities (Prince William and Yao Ming) are calling on to protect them. So students are guided to enhance the awareness of protecting wildlife and try to take part in some volunteer activities of protecting wildlife.1. Predict the content by using visuals. 2. Learn to use the sentences such as “I’m concerned about.... But now they are in danger. I want to know the reasons/why./ What can we do to protect them ?3. Learn from the stars like Prince William and Yao Ming and enhance the awareness of protecting wildlife.4. Guide students to try to put forward the solutions to the problems of wildlife protection and then discuss them with partners and present the results of discussion.5. Master the pronunciation of stressed syllables.1. Learn from the stars like Prince William and Yao Ming and enhance the awareness of protecting wildlife.2. Guide students to try to put forward the solutions to the problems of wildlife protection and then discuss them with partners and present the results of discussion.3. Learn to use the sentences such as “I’m concerned about.... But now they are in danger. I want to know the reasons/why./ What can we do to protect them ?4. Master the pronunciation of stressed syllables.Part A Listening and Speaking--- How to save endangered wildlifeStep 1 Lead in1. Point at the pictures on P14 and ask Q1: What message do these posters share?

  • 新人教版高中英语必修2Unit 3 The Internet-Listening &Speaking&Talking教案二

    新人教版高中英语必修2Unit 3 The Internet-Listening &Speaking&Talking教案二

    From the pictures in the text and the title--- choose the best app, we can know that this part is about how to save money by using apps.Step 2 While-listening1. Laura and Xiao Bo are talking about apps. Listen to their conversation and find out what apps they want.Xiao Bo is looking for a(n) exercise app to help him get in shape.Laura would like an app for getting rich and another that will make her grades better.2. Listen again. Are the sentences true T or false F?1). Both of Xiao Bo's apps keep track of the steps he takes._____2). Xiao Bo's second app can help him make a fitness plan._____3). Laura needs an app that will help her get discounts.______4). Laura needs an app that will add money to her bank account._______F T F T3. Listen once more and tick the sentence you hear. Underline the words used to express predictions, guesses, and beliefs.Predictions, Guesses, and Beliefs________It might help me walk more.________My guess is that it wouldn't work.________I imagine this app would help me get fit faster________I suppose that would be good.________I guess you could save a little with this app.________I suppose there would be some problems, too.________I believe this app could help me get thinner.

  • 新人教版高中英语必修2Unit 4 History and Traditions-Listening&Speaking&Talking教案一

    新人教版高中英语必修2Unit 4 History and Traditions-Listening&Speaking&Talking教案一

    This unit is about history and traditions. From the opening page, we can know that this unit will introduce the history and traditions around the world. As Marcus Garvey says “A people without the knowledge of their past history, origin and culture is like a tree without roots”, it is important for students to realize the importance and value of knowing the history and traditions and their further meanings. And this part ( listening and speaking ) is divided into two parts: Part A---share views on historic sites, Part B ---talk about a visit to a historic tourist destination. By talking with a foreigner, the speakers introduce the historic attractions and their cultures. Part A is that William, a British student, who was going to visit the Confucius Temple and a Chinese student, Xiao Kong, who was going to the Confucius Temple to meet with the members of the research group, went together and exchanged their views on the Confucius Temple, Confucius, Confucius' descendants and Confucius' educational thoughts. Part B is a conversation between Xiao Yan, a youth hostel receptionist and Paul, a backpacker about the feelings and experience after visiting the Chinese famous tourist attraction Pingyao.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 talk about historic spots and great person.3. Instruct students to use functional sentences of showing one’s excitement, surprise and disappointment.1. Guide students to understand the content of listening texts in terms of the whole and key details; 2. Cultivate students' ability to discuss with their peers the related topics.3. Enable students to use the functional items of showing one’s excitement, surprise and disappointment.

  • 新人教版高中英语必修2Unit 3 The Internet-Reading For Writing教案一

    新人教版高中英语必修2Unit 3 The Internet-Reading For Writing教案一

    ⑦identity theft 身份盗窃⑧chat room 聊天室⑨draft your blog post 起草博客帖子⑩post embarrassing photos 张贴尴尬照片 【话题句式】 1. How do you stay safe online and avoid bad experiences on the Internet? 你如何在网上保持安全, 避免在网上的不良经历? 2. I’m not an expert, but many years as a blogger have taught me a thing or two. 我不是专家, 但作为一个博主, 我已经学了好几年了。 3. If you see or read something that makes you feel uncomfortable, leave the site immediately. 如果你看到或读到一些让你觉得不舒服的东西, 立即离开这个网站。4. Don’t give out your address or phone number. 别告诉别人你的地址或电话号码。 5. Identity theft is a common and serious problem. 身份盗窃是一个常见而严重的问题。6. Being online is no excuse for being rude, and you don’t want to become a target for a troll or cyberbully. 上网并不是无礼的借口, 你也不想成为发挑衅帖子的人或网络恶霸的目标。 7. Trolls often use several false names so that they can stay on a site. 发挑衅帖子的人经常使用几个假名, 这样他们就可以留在一个网站上。8. However, the more polite you are, the less likely it is you will be attacked. 然而, 你越有礼貌, 你被攻击的可能性就越小。

  • 新人教版高中英语必修2Unit 4 History and Traditions-Listening&Speaking&Talking教案二

    新人教版高中英语必修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.

  • 人教版高中地理必修2人口数量的变化教案

    人教版高中地理必修2人口数量的变化教案

    【教学目标】 1.理解人口数量在社会的发展过程中的变化趋势,并能一一解释其原因;2.理解发达国家和发展中国家人口增长的差异和成因,并理解不同国家有不同的人口政策;3.运用图表分析世界人口增长模式的特点,并比较人口增长模式的时间和空间的差异;4.通过学习,能读懂并分析人口增长坐标图;同时能辩证地认识人口增长的不同状况采取的人口政策也不同。【教学重、难点及解决办法] 】重点:分析并比较人口增长模式在时间和空间上的差异难点:理解人口增长模式的三个指标解决方法:读图分析比较法 调查研究法 案例分析法 自主学习与合作探究 【教学准备】多媒体课件缺勤登记:【板书设计】第一节人口数量的变化第一节 人口数量的变化一、人口的自然增长(一)人口在数量变化在时间上是不均匀的(二)世界人口增长在空间上的差异——不均衡二、人口的增长模式及其转变

  • 人教版高中地理必修2人口合理容量教案

    人教版高中地理必修2人口合理容量教案

    (1)请同学们结合日常生活实例和教材分析说明人类要在世界各地消除贫困并保持人口的合理容量任务的艰巨性?(2)采取何种措施才能更好的解决这一问题的出现?教师总结(1)现实中的人口问题(如人口过快增长、人口城市化和人口老龄化等)引发了严重的资源问题和环境问题。①发达国家的人均消耗资源量很大,索取资源和转嫁有害生产的地域超出了本国的范围。②发展中国家不仅人口数量多,人均消费水平低,而且一些国家的人口仍在快速增长。若在现有的经济基础上,把发展中国家人均生活质量提高到与发达国家相当的水平,所引发的资源短缺和环境问题将会相当严重,解决的难度也很大。(2)I就整个世界来说:①国际社会要倡导各国,尤其发展中国家要尽最大可能把人口控制在合理的规模之内;②建立公平的秩序,保证大多数人拥有不断追求高水平生活质量的平等权利。

  • 人教版高中地理必修2人地关系思想的演变教案

    人教版高中地理必修2人地关系思想的演变教案

    2.由于附近金矿生产废弃物尾矿砂的堆积,孙家村的大沟里十几年来就吃掉了近百亩土地,使人均耕地下降到0.03公顷。村里和矿上共同商量,共同开发复垦,由矿上出钱,村里出劳力、机械,运来“客土”覆盖到尾矿填平的沟壑上,形成耕地。十年来,通过这种方式恢复耕地15.335公顷,不仅解决了尾矿污染问题,而且村里耕地由25公顷多增加到40公顷。【思考】分析以上两个例子,哪一个体现了可持续发展的原则,为什么?【分析】第二个材料体现了可持续发展。因为材料1用农田堆放垃圾会破坏土地肥力,影响农业生产,又污染环境,危害村民健康。这种行为目光短浅,只顾眼前利益,没有考虑长远发展。材料2既解决了尾矿污染问题,又增加了耕地面积,耕地是可再生资源,利用得当,可为村民提供农产品,解决温饱同时创造经济效益,达到良性循环。所以说保护环境就是挽救人类,我们要将这种意识转化为自身行为,使人地关系走向和谐。

  • 人教版高中地理必修2人口的空间变化教案

    人教版高中地理必修2人口的空间变化教案

    影响我国古代人口大规模迁移的因素,与影响我国近几十年人口迁移的因素有何不同?(古代:战乱,其次为开疆拓土、流放、戍边等。现代:国家政策、社会变革、经济发展、个人需求等。)2、为什么有这样的不同?(古代人口迁移受统治者及其行政力量的束缚。由于自给自足的经济十分脆弱,加之频繁的战争以及自然灾害等影响,人民难以安居乐业,不得不背井离乡大批迁移。近几十年来随着社会经济的发展、贸易的往来和交通的便捷,我国人口迁移不仅数量增加,而且频率加快,使各地人们的交往更加密切。)教师总结:从古今中外的人口迁移现象中,我们可以看出在人类历史早期人口迁移中重要的因素是什么?(自然因素)现在什么因素起重要作用?(经济因素)。但是在某种特定的时空条件下,任何一种因素都有可能成为促使人口迁移的决定性因素。【作业设计】查阅49年以来中国历年的人口数据资料,绘制人口增长的统计图表,探究中国人口增长的发展趋势

  • 人教版高中政治必修2我国的宗教政策教案

    人教版高中政治必修2我国的宗教政策教案

    (1)宗教有它自身的发展规律,不能简单的用行政力量去消灭或发展宗教,实行宗教信仰自由政策是遵循宗教发展规律,科学处理宗教问题。(2)宗教信仰自由是宪法赋予公民的民主权利,实行宗教信仰自由政策有利于加强信教群众与不信教群众的团结,引导宗教与社会主义社会相适应。2、弘扬科学精神我国是在马列主义、毛泽东思想、邓小平理论、三个代表重要思想指引下的社会主义国家,要建设社会主义物质文明、政治文明,也要建设社会主义精神文明。加强对人民群众的科学世界观和无神论教育,形成文明、健康、崇尚科学的社会风尚,逐步消除宗教存在的社会根源何认识根源,在保护宗教信仰自由的同时,创造宗教消亡的条件,这是解决在教问题的根本途径。3、中学生作为中国特色社会主义事业未来的建设者,要用辩证唯物主义和历史主义以及现代科学文化知识武装自己,弘扬科学精神,树立科学世界观,承担起建设祖国、振兴中华的光荣历史使命。

  • 人教版高中政治必修2我国的宗教政策教案

    人教版高中政治必修2我国的宗教政策教案

    (一)知识目标识记:宗教信仰自由的含义。理解:(1)社会主义条件下宗教存在的长期性;(2)理解我国实行宗教信仰自由的内容;(3)依法加强对宗教事务管理的有关规定。(4)积极引导宗教与社会主义社会相适应。(二)能力目标能运用马克思主义关于宗教的基本观点,分析说明我国实行宗教信仰自由的正确性和必要性。(三)情感、态度与价值观目标通过学习,加强宗教的政策观念,自觉抵制和反对各种迷信活动,特别是认清法轮功的邪教本质。三、教学重点难点全面理解和贯彻宗教信仰自由政策既是重点又是难点,教学中紧紧抓住中央一再强调的三句话:(1)全面贯彻宗教政策;(2)加强对宗教事务管理:(3)引导宗教与社会主义社会相适应。四、学情分析这是本课的难点。我国是多民族的国家,也是多宗教的国家,特别是宗教对一些少数民族有广泛而深远的影响。我们东部地区的学生,很多人还存在疑惑:我们社会主义国家为什么还允许宗教存在,实行宗教信仰自由政策呢?

  • 人教版高中地理必修1宇宙中的地球教案

    人教版高中地理必修1宇宙中的地球教案

    从质量、体积、平均密度、公转与自转周期等各方面,地球没有一项是最大值或最小值,这说明地球仅仅是太阳系中一颗最普通不过的一颗行星。2、地球又是一颗特殊的行星。问题 :为什么?因为地球是目前我们已知的唯一存在生物,特点是存在高级智慧生物的天体。问题:为什么地球上会存在生命?原因:(1)地球所处的宇宙环境来说:地球处于一种相对安全的宇宙环境。例:A、九大行星公转的同向性、同面 性、及公 转轨道的近圆性。B 太阳光照条件的稳定性。从地球产生到地球上有生物,几十亿年期间,太阳 没有明显的变化,地球所处的光照条件一直较稳定,生命演化没有中断。(2)地球自身的物质条件:例:A 日地距离适中,形成了适宜的温度:日地距离适中,地球表面平均温度15度,适合生物的生存。(扩展:地球自转速度适中,大气层的保温效应)B 地球质量与体积适中,使地球有了适合的大气条件。C 原始海洋的形成 :使 生命的出现成为可能。

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