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新人教版高中英语必修3Unit 2 Morals and Virtues教学设计四
3.Teachers ask different groups to report the answers to the questions and ask them to try different sentence patterns.The teacher added some sentence patterns for students to refer to when writing.Step 4 Writing taskActivity 51.Write the first draft.Students first review the evaluation criteria in activity 5, and then independently complete the draft according to the outline of activity 4, the answers to the questions listed in the group discussion and report, and the reference sentence pattern.2.Change partners.The teacher guides the students to evaluate their partner's composition according to the checklist of activity 5 and proposes Suggestions for modification.3.Finalize the draft.Based on the peer evaluation, students revise their own compositions and determine the final draft.Finally, through group recommendation, the teacher selects excellent compositions for projection display or reading aloud in class, and gives comments and Suggestions.Step 5 Showing writingActivity 5T call some Ss to share their writing.Step 6 Homework1. Read the passage in this section to better understand the passage.2. Carefully understand the hierarchical structure of the article, and deeply understand the plot of the story according to the causes, process and results;3. Independently complete the relevant exercises in the guide plan.1、通过本节内容学习，学生是否理解和掌握阅读文本中的新词汇的意义与用法；2、通过本节内容学习，学生能否通过人物言行的对比分析道德故事的深层内涵；3、通过本节内容学习，学生能否根据故事的起因、经过和结果来深入理解故事的情节，从而了解文章的层次结构；4、结合现实生活案例发表自己的见解和看法,写一篇观点明确、层次分明的故事评论。
新人教版高中英语必修3Unit 2 Morals and virtues教学设计一
(2) students are divided into groups according to the requirements of activity 3. Each student shares a story of personal experience or hearing-witnessing kindness, and then selects the most touching story in the group and shares it with the whole class. Before the students share the story, the teacher can instruct them to use the words and sentence patterns in the box to express. For example, the words in the box can be classified:Time order: first of all, then, after that, later, finally logical relationship :so, however, although, butTeachers can also appropriately add some transitional language to enrich students' expression:Afterwards, afterwards, at last, in the end, eventuallySpatial order: next to, far from, on the left, in front ofOtherwise, nevertheless, as a result, therefore, furthermore, in addition, as well asSummary: in a word, in short, on the whole, to sum up, in briefStep 8 Homework1. Understand the definition of "moral dilemma" and establish a correct moral view;2. Accumulate vocabulary about attitudes and emotions in listening texts and use them to express your own views;3. Complete relevant exercises in the guide plan.1、通过本节内容学习，学生能否理解理解“道德困境”的定义；2、通过本节内容学习，学生能否通过说话人所表达的内容、说话的语气、语调等来判断其态度和情绪；3、通过本节内容学习，学生能否针对具体的道德困境发表自己的看法和见解，能否掌握听力理训练中的听力策略。
新人教版高中英语必修3Unit 3 Diverse Cultures教学设计三
The price is the same as(the price was)before the war.价格与战前相同。(4)定语从句中的“关系代词＋助动词be”可以省略。The ticket(that/which was)booked by his sister has been sent to him.他妹妹订的那张票已送到了他那里。Step 5 PracticeActivity 3(1) Guide students to complete the four activities in the Using Structures part of exercise book, in which activities 1 and 2 focus on ellipsis in dialogue answers, activity 3 focus on signs and headlines, two typical situations where ellipsis is used, and activity 4 focus on ellipsis in diary, an informal style.(2) Combine the examples in the above activities, ask students to summarize the omitted situations in groups, and make their own summary into a poster, and post it on the class wall after class to share with the class.(This step should give full play to the subjectivity of students, and teachers should encourage students to conclude different ellipsis phenomena according to their own understanding, they can conclude according to the different parts omitted in the sentence.)Step 6 Homework1. Understand and master the usages of ellipsis;2. Finish the other exercises in Using structures of Workbook.1、通过本节内容学习，学生是否理解和掌握省略的用法；2、通过本节内容学习，学生能否根据上下文语境或情景恢复句子中省略的成分，体会使用省略的效果；3、通过本节内容学习，学生能否独立完成练习册和导学案中的相关练习。
新人教版高中英语必修3Unit 3 Diverse Cultures教学设计二
(2)Consolidate key vocabulary.Ask the students to complete the exercises of activity 6 by themselves. Then ask them to check the answers with their partners.(The first language:Damage of the 1906 San Francisco earthquake and fire.A second language: Yunnan - one of the most diverse provinces in China).Step 5 Language points1. The teacher asks the students to read the text carefully, find out the more words and long and difficult sentences in the text and draw lines, understand the use of vocabulary, and analyze the structure of long and difficult sentences.2. The teacher explains and summarizes the usage of core vocabulary and asks the students to take notes.3. The teacher analyzes and explains the long and difficult sentences that the students don't understand, so that the students can understand them better.Step 6 Homework1. Read the text again, in-depth understanding of the text;2. Master the use of core vocabulary and understand the long and difficult sentences.3. Complete relevant exercises in the guide plan.1、通过本节内容学习，学生是否理解和掌握阅读文本中的新词汇的意义与用法；2、通过本节内容学习，学生能否结合文本特点了解文章的结构和作者的写作逻辑；3、通过本节内容学习，学生能否了解旧金山的城市风貌、文化特色，以及加利福尼亚州的历史，体会多元文化对美国的影响。
新人教版高中英语必修3Unit 3 Diverse Cultures教学设计四
该板块的活动主题是“介绍一个有显著文化特征的地方”( Describe a place with distinctive cultural identity)。该板块通过介绍中国城继续聚焦中国文化。本单元主题图呈现的是旧金山中国城的典型景象, Reading and Thinking部分也提到中国城,为该板块作铺垫。介绍中国城的目的主要是体现中国文化与美国多元文化的关系,它是美国多元文化的重要组成部分。中国城也是海外华人的精神家园和传播中国文化的重要窗口,外国人在中国城能近距离体验中国文化。1. Read the text to understand the cultural characteristics of Chinatown in San Francisco and the relationship between Chinese culture and American multiculturalism;2. Through reading, learn to comb the main information of the article, understand the author's writing purpose and writing characteristics;3. Learn to give a comprehensive, accurate, and organized description of the city or town you live in;Learn to revise and evaluate your writing.Importance:1. Guide the students to read the introduction of Chinatown in San Francisco and grasp its writing characteristics;2. Guide students to introduce their city or town in a comprehensive, accurate and organized way;3. Learn to comb the main information of the article, understand the author's writing purpose, and master the core vocabulary.
新人教版高中英语必修3Unit 3 Diverse Cultures教学设计一
Activity 81.Grasp the main idea of the listening.Listen to the tape and answer the following questions:Who are the two speakers in the listening? What is their relationship?What is the main idea of the first part of the listening? How about the second part?2.Complete the passage.Ask the students to quickly review the summaries of the two listening materials in activity 2. Then play the recording for the second time.Ask them to complete the passage and fill in the blanks.3.Play the recording again and ask the students to use the structure diagram to comb the information structure in the listening.(While listening, take notes. Capture key information quickly and accurately.)Step 8 Talking Activity 91.Focus on the listening text.Listen to the students and listen to the tape. Let them understand the attitudes of Wu Yue and Justin in the conversation.How does Wu Yue feel about Chinese minority cultures?What does Justin think of the Miao and Dong cultures?How do you know that?2.learn functional items that express concerns.Ask students to focus on the expressions listed in activity. 3.And try to analyze the meaning they convey, including praise (Super!).Agree (Exactly!)"(You're kidding.!)Tell me more about it. Tell me more about it.For example, "Yeah Sure." "Definitely!" "Certainly!" "No kidding!" "No wonder!" and so on.4.Ask the students to have conversations in small groups, acting as Jsim and his friends.Justin shares his travels in Guizhou with friends and his thoughts;Justin's friends should give appropriate feedback, express their interest in relevant information, and ask for information when necessary.In order to enrich the dialogue, teachers can expand and supplement the introduction of Miao, dong, Lusheng and Dong Dage.After the group practice, the teacher can choose several groups of students to show, and let the rest of the students listen carefully, after listening to the best performance of the group, and give at least two reasons.
新人教版高中英语选修2Unit 3 Learning about Language教学设计
1. We'll need ten months at least to have the restaurant decorated.2.Some traditional Chinese dishes from before the Ming Dynasty are still popular today.3.My grandpa's breakfast mainly includes whole grain biscuits and a glass of milk.4.People in this area would eat nearly a kilo of cheese per week.5. We enjoyed a special dinner in a fancy restaurant where the waiters all wore attractive suits.6. He prefers this brand of coffee which, as he said, has an unusually good flavor.Key:1. at a minimum 2. prior to3. consist of4. consume5. elegant6. exceptionalStep 5：Familiarize yourself with some food idioms by matching the meaning on the right with the colored words on the left.1.Public concern for the health of farm animals has mushroomed in the UK2.Anderson may be young but he's certainly rolling to doing dough!3.George is a popular lecturer. He often peppers his speech with jokes.4.As the person to bring home the bacon, he needs to find a stable job.5 He is often regarded as a ham actor for his over emphasized facial expressions. The media reported that these companies had treated pollution as a hot potato. 6.The media reported that these companies had treated pollution as a hot potato.7.Don't worry about the test tomorrow. It's going to be a piece of cake!8. It's best to fold the swimming ring when it is as flat as a pancake.A. completely flatB. something that is very easy to do C.an issue that is hard to deal withD.to include large numbers of somethingE.to earn on e's living to support a familyF. wealthyG.to rapidly increase in numberH. an actor who performs badly, especially by over emphasizing emotions
新人教版高中英语选修2Unit 2 Reading and thinking教学设计
Her tutor told her to acknowledge __________ other people had said if she cited their ideas, and advised her _______（read） lots of information in order to form __________wise opinion of her own.Now halfway __________ her exchange year, Xie Lei felt much more at home in the UK. She said __________ (engage) in British culture had helped and that she had been__________ (involve) in social activities. She also said while learning about business, she was acting as a cultural messenger __________（build） a bridge between the two countries. keys:Xie Lei, a 19yearold Chinese student, said goodbye to her family and friends in China and boarded (board) a plane for London six months ago in order to get a business qualification. She was ambitious(ambition) to set up a business after graduation. It was the first time that she had left (leave) home.At first, Xie Lei had to adapt to life in a different country. She chose to live with a host family, who can help with her adaptation (adapt) to the new culture. When she missed home, she felt comforted (comfort) to have a second family. Also Xie Lei had to satisfy academic requirements. Her tutor told her to acknowledge what other people had said if she cited their ideas, and advised her to read lots of information in order to form a wise opinion of her own.Now halfway through her exchange year, Xie Lei felt much more at home in the UK. She said engaging (engage) in British culture had helped and that she had been involved (involve) in social activities. She also said while learning about business, she was acting as a cultural messenger building a bridge between the two countries.
新人教版高中英语选修2Unit 2 Using langauge-Listening教学设计
? B: Absolutely! Getting involved with Chinese cultural activities there definitely helped a lot. I got to practice my Chinese on a daily basis, and I could learn how native Chinese speakers spoke.? A: What do you feel is your biggest achievement?? B: Learning Chinese characters! I have learnt about 1,500 so far. When I first started, I didn't think it was even going to be possible to learn so many, but now I find that I can read signs, menus, and even some easy newspaper articles.? A: What are you most keen on?? B: I've really become keen on learning more about the Chinese culture, in particular Chinese calligraphy. As I have learnt Chinese characters, I have developed a great appreciation for their meaning. I want to explore Chinese characters by learning how to write them in a more beautiful way. ? A: Finally, what do you want to say to anyone interested in learning Chinese?? I have really become keen on learning more about the Chinese culture, in particular Chinese Calligraphy. As I have learnt Chinese character, I have developed a great appreciation for their meaning. I want to explore Chinese characters by learning how to write them in a more beautiful way.? A: Finally, what do you want to say to anyone interested in learning Chinese?? B: I'd say, give it a shot! While some aspects may be difficult, it is quite rewarding and you will be happy that you tried.? A: Thanks for your time. ? B:You're welcome.
新人教版高中英语选修2Unit 3 Using langauge-Listening教学设计
1． How is Hunan cuisine somewhat different from Sichuan cuisine?The heat in Sichuan cuisine comes from chilies and Sichuan peppercorns. Human cuisine is often hotter and the heat comes from just chilies.2.What are the reasons why Hunan people like spicy food?Because they are a bold people. But many Chinese people think that hot food helps them overcome the effects of rainy or wet weather.3.Why do so many people love steamed fish head covered with chilies?People love it because the meat is quite tender and there are very few small bones.4.Why does Tingting recommend bridge tofu instead of dry pot duck with golden buns?Because bridge tofu has a lighter taste.5 .Why is red braised pork the most famous dish?Because Chairman Mao was from Hunan, and this was his favorite food.Step 5: Instruct students to make a short presentation to the class about your choice. Use the example and useful phrases below to help them.? In groups of three, discuss what types of restaurant you would like to take a foreign visitor to, and why. Then take turns role-playing taking your foreign guest to the restaurant you have chosen. One of you should act as the foreign guest, one as the Chinese host, and one as the waiter or waitress. You may start like this:? EXAMPLE? A: I really love spicy food, so what dish would you recommend?? B: I suggest Mapo tofu.? A: Really ? what's that?
新人教版高中英语选修2Unit 4 Using langauge-Listening教学设计
The theme of the listening section is " talking about scenery and culture along a journey."The part is designed to further lead the students to understand Canadian natural geography and social environment, and integrated into the cultural contrast by mentioning the long train journey from Beijing to Moscow routes. On this basis, the part activates students related travel experience, lets the student serial dialogue, guides the student to explore further the pleasure and meaning of the long journey, and Chinese and foreign cultural comparison.The part also provides a framework for the continuation of the dialogue, which is designed to provide a framework for students to successfully complete their oral expressions, and to incorporate an important trading strategy to end the dialogue naturally.1. Help students to understand and master some common English idioms in the context, and experience the expression effect of English idioms.2. Guide the students to understand the identity of different people in the listening context, and finish the dialogue according to their own experience.3. Instruct the students to use appropriate language to express surprise and curiosity about space and place in the dialogue, and master the oral strategy of ending the dialogue naturally.1. Instruct students to grasp the key information and important details of the dialogue.2. Instruct students to conduct a similar talk on the relevant topic.
新人教版高中英语选修2Unit 5 Reading and thinking教学设计
The theme of this activity is to learn the first aid knowledge of burns. Burns is common in life, but there are some misunderstandings in manual treatment. This activity provides students with correct first aid methods, so as not to take them for granted in an emergency. This section guides students to analyze the causes of scald and help students avoid such things. From the perspective of text structure and collaborative features, the text is expository. Expository, with explanation as the main way of expression, transmits knowledge and information to readers by analyzing concepts and elaborating examples. This text arranges the information in logical order, clearly presents three parts of the content through the subtitle, accurately describes the causes, types, characteristics and first aid measures of burns, and some paragraphs use topic sentences to summarize the main idea, and the level is very clear.1. Guide students to understand the causes, types, characteristics and first aid methods of burns, through reading2. Enhance students’ ability to deal withburnss and their awareness of burns prevention3. Enable students to improve the ability to judge the types of texts accurately and to master the characteristics and writing techniques of expository texts.Guide students to understand the causes, types, characteristics and first aid methods of burns, through readingStep1: Lead in by discussing the related topic:1. What first-aid techniques do you know of ?CPR; mouth to mouth artificial respiration; the Heimlich Manoeuvre
人教A版高中数学必修一对数的运算教学设计（1）
本节课是新版教材人教A版普通高中课程标准实验教科书数学必修1第四章第4.3.2节《对数的运算》。其核心是弄清楚对数的定义，掌握对数的运算性质，理解它的关键就是通过实例使学生认识对数式与指数式的关系，分析得出对数的概念及对数式与指数式的 互化，通过实例推导对数的运算性质。由于它还与后续很多内容，比如对数函数及其性质,这也是高考必考内容之一，所以在本学科有着很重要的地位。解决重点的关键是抓住对数的概念、并让学生掌握对数式与指数式的互化；通过实例推导对数的运算性质，让学生准确地运用对数运算性质进行运算，学会运用换底公式。培养学生数学运算、数学抽象、逻辑推理和数学建模的核心素养。1、理解对数的概念，能进行指数式与对数式的互化；2、了解常用对数与自然对数的意义，理解对数恒等式并能运用于有关对数计算。
人教A版高中数学必修一函数的概念教学设计（2）
函数在高中数学中占有很重要的比重，因而作为函数的第一节内容，主要从三个实例出发，引出函数的概念.从而就函数概念的分析判断函数，求定义域和函数值，再结合三要素判断函数相等.课程目标1.理解函数的定义、函数的定义域、值域及对应法则。2.掌握判定函数和函数相等的方法。3.学会求函数的定义域与函数值。数学学科素养1.数学抽象：通过教材中四个实例总结函数定义；2.逻辑推理：相等函数的判断；3.数学运算：求函数定义域和求函数值；4.数据分析：运用分离常数法和换元法求值域；5.数学建模：通过从实际问题中抽象概括出函数概念的活动，培养学生从“特殊到一般”的分析问题的能力，提高学生的抽象概括能力。重点：函数的概念，函数的三要素。难点：函数概念及符号y=f(x)的理解。
人教A版高中数学必修一任意角教学设计（2）
学生在初中学习了 ～ ，但是现实生活中随处可见超出 ～ 范围的角.例如体操中有“前空翻转体 ”，且主动轮和被动轮的旋转方向不一致.因此为了准确描述这些现象，本节课主要就旋转度数和旋转方向对角的概念进行推广.课程目标1.了解任意角的概念.2.理解象限角的概念及终边相同的角的含义．3.掌握判断象限角及表示终边相同的角的方法．数学学科素养1.数学抽象：理解任意角的概念，能区分各类角；2.逻辑推理：求区域角；3.数学运算：会判断象限角及终边相同的角.重点：理解象限角的概念及终边相同的角的含义；难点：掌握判断象限角及表示终边相同的角的方法．教学方法：以学生为主体，采用诱思探究式教学，精讲多练。教学工具：多媒体。一、 情景导入初中对角的定义是：射线OA绕端点O按逆时针方向旋转一周回到起始位置，在这个过程中可以得到 ～ 范围内的角.但是现实生活中随处可见超出 ～ 范围的角.例如体操中有“前空翻转体 ”，且主动轮和被动轮的旋转方向不一致.
人教A版高中数学必修一诱导公式教学设计（2）
本节主要内容是三角函数的诱导公式中的公式二至公式六，其推导过程中涉及到对称变换，充分体现对称变换思想在数学中的应用，在练习中加以应用，让学生进一步体会 的任意性；综合六组诱导公式总结出记忆诱导公式的口诀：“奇变偶不变，符号看象限”，了解从特殊到一般的数学思想的探究过程，培养学生用联系、变化的辩证唯物主义观点去分析问题的能力。诱导公式在三角函数化简、求值中具有非常重要的工具作用，要求学生能熟练的掌握和应用。课程目标1.借助单位圆，推导出正弦、余弦第二、三、四、五、六组的诱导公式，能正确运用诱导公式将任意角的三角函数化为锐角的三角函数，并解决有关三角函数求值、化简和恒等式证明问题2.通过公式的应用，了解未知到已知、复杂到简单的转化过程，培养学生的化归思想，以及信息加工能力、运算推理能力、分析问题和解决问题的能力。
人教版高中数学选修3超几何分布教学设计
探究新知问题1：已知100件产品中有8件次品，现从中采用有放回方式随机抽取4件．设抽取的4件产品中次品数为X，求随机变量X的分布列.（1）：采用有放回抽样，随机变量X服从二项分布吗？采用有放回抽样，则每次抽到次品的概率为0.08，且各次抽样的结果相互独立,此时X服从二项分布,即X～B(4，0.08).（2）：如果采用不放回抽样，抽取的4件产品中次品数X服从二项分布吗？若不服从，那么X的分布列是什么？不服从，根据古典概型求X的分布列.解：从100件产品中任取4件有 C_100^4 种不同的取法，从100件产品中任取4件，次品数X可能取0,1,2,3,4.恰有k件次品的取法有C_8^k C_92^(4-k)种.一般地，假设一批产品共有N件，其中有M件次品．从N件产品中随机抽取n件(不放回），用X表示抽取的n件产品中的次品数，则X的分布列为P(X＝k）＝CkM Cn－kN－M CnN ，k＝m，m＋1，m＋2，…，r.其中n，N，M∈N*，M≤N，n≤N，m＝max{0，n－N＋M}，r＝min{n，M}，则称随机变量X服从超几何分布．
人教版高中数学选修3二项式定理教学设计
二项式定理形式上的特点(1)二项展开式有n+1项,而不是n项.(2)二项式系数都是C_n^k(k=0,1,2,…,n),它与二项展开式中某一项的系数不一定相等.(3)二项展开式中的二项式系数的和等于2n,即C_n^0+C_n^1+C_n^2+…+C_n^n=2n.(4)在排列方式上,按照字母a的降幂排列,从第一项起,次数由n次逐项减少1次直到0次,同时字母b按升幂排列,次数由0次逐项增加1次直到n次.1．判断(正确的打“√”，错误的打“×”)(1)(a＋b)n展开式中共有n项． ( )(2)在公式中，交换a，b的顺序对各项没有影响． ( )(3)Cknan－kbk是(a＋b)n展开式中的第k项． ( )(4)(a－b)n与(a＋b)n的二项式展开式的二项式系数相同． ( )[解析] (1)× 因为(a＋b)n展开式中共有n＋1项．(2)× 因为二项式的第k＋1项Cknan－kbk和(b＋a)n的展开式的第k＋1项Cknbn－kak是不同的，其中的a，b是不能随便交换的．(3)× 因为Cknan－kbk是(a＋b)n展开式中的第k＋1项．(4)√ 因为(a－b)n与(a＋b)n的二项式展开式的二项式系数都是Crn.[答案] (1)× (2)× (3)× (4)√
人教版高中数学选修3全概率公式教学设计
2.某小组有20名射手，其中1，2，3，4级射手分别为2，6，9，3名.又若选1，2，3，4级射手参加比赛，则在比赛中射中目标的概率分别为0.85，0.64，0.45，0.32，今随机选一人参加比赛，则该小组比赛中射中目标的概率为________. 【解析】设B表示“该小组比赛中射中目标”，Ai(i=1，2，3，4)表示“选i级射手参加比赛”，则P(B)= P(Ai)P(B|Ai)= 2/20×0.85+ 6/20 ×0.64+ 9/20×0.45+ 3/20×0.32=0.527 5.答案：0.527 53.两批相同的产品各有12件和10件，每批产品中各有1件废品，现在先从第1批产品中任取1件放入第2批中，然后从第2批中任取1件，则取到废品的概率为________. 【解析】设A表示“取到废品”，B表示“从第1批中取到废品”，有P(B)= 112，P(A|B)= 2/11 ，P(A| )= 1/11所以P(A)=P(B)P(A|B)+P( )P(A| )4．有一批同一型号的产品，已知其中由一厂生产的占 30%, 二厂生产的占 50% , 三厂生产的占 20%, 又知这三个厂的产品次品率分别为2% , 1%, 1%，问从这批产品中任取一件是次品的概率是多少？
人教版高中数学选修3条件概率教学设计
(2)方法一:第一次取到一件不合格品,还剩下99件产品,其中有4件不合格品,95件合格品,于是第二次又取到不合格品的概率为4/99,由于这是一个条件概率,所以P(B|A)=4/99.方法二:根据条件概率的定义,先求出事件A,B同时发生的概率P(AB)=(C_5^2)/(C_100^2 )=1/495,所以P(B|A)=(P"(" AB")" )/(P"(" A")" )=(1/495)/(5/100)=4/99.6.在某次考试中,要从20道题中随机地抽出6道题,若考生至少答对其中的4道题即可通过;若至少答对其中5道题就获得优秀.已知某考生能答对其中10道题,并且知道他在这次考试中已经通过,求他获得优秀成绩的概率.解:设事件A为“该考生6道题全答对”,事件B为“该考生答对了其中5道题而另一道答错”,事件C为“该考生答对了其中4道题而另2道题答错”,事件D为“该考生在这次考试中通过”,事件E为“该考生在这次考试中获得优秀”,则A,B,C两两互斥,且D=A∪B∪C,E=A∪B,由古典概型的概率公式及加法公式可知P(D)=P(A∪B∪C)=P(A)+P(B)+P(C)=(C_10^6)/(C_20^6 )+(C_10^5 C_10^1)/(C_20^6 )+(C_10^4 C_10^2)/(C_20^6 )=(12" " 180)/(C_20^6 ),P(E|D)=P(A∪B|D)=P(A|D)+P(B|D)=(P"(" A")" )/(P"(" D")" )+(P"(" B")" )/(P"(" D")" )=(210/(C_20^6 ))/((12" " 180)/(C_20^6 ))+((2" " 520)/(C_20^6 ))/((12" " 180)/(C_20^6 ))=13/58,即所求概率为13/58.