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《Colours》作业设计方案（第一课时）一、作业目标本次作业旨在帮助学生巩固颜色词汇，提高英语听说能力，同时培养他们用英语表达事物的兴趣和自信心。
二、作业内容1. 词汇练习：学生需复习并识记红色（red）、蓝色（blue）、绿色（green）、黄色（yellow）等基本颜色词汇。
可以通过抄写、听录音跟读等方式进行。
2. 绘画作业：学生需用所学的颜色画一幅简单的图画，如画一个红色的苹果、蓝色的气球等。
要求图画中至少包含两种颜色，并尝试尽可能多地使用不同的颜色。
3. 口语练习：学生需与同学用英语描述自己的画作，包括画了什么、用了哪些颜色等。
可以两人一组进行对话，也可以单独完成。
4. 阅读理解：学生需阅读一篇与颜色相关的短文，如描述颜色的由来、颜色的含义等，并回答文后问题。
三、作业要求1. 按时完成：请学生在课后尽快完成作业，并确保在次日上课前提交。
2. 认真对待：作业是检验学生对课堂知识的掌握程度，请学生认真对待，确保作业质量。
3. 独立完成：作业中涉及的知识点已在课堂上讲解，请学生独立完成，不要寻求他人帮助。
4. 反馈与交流：学生可与同学互相交流、帮助，共同提高。
如有疑问，请及时向老师反馈，以便老师及时了解学生的学习情况。
四、作业评价1. 评价标准：作业完成情况、准确性、创造力、语言表达能力等。
2. 评价方式：老师将根据学生提交的作业情况进行评分，同时关注学生在作业中的表现和进步。
对于表现优秀、进步明显的学生，将给予一定的奖励或表扬。
3. 反馈机制：对于作业中存在的问题，老师将在下次上课时进行讲解和指导，并提供相应的帮助和支持。
同时，学生也可在课后向老师咨询，寻求帮助。
五、作业反馈本次作业大部分学生能够按时完成，但在词汇抄写和口语表达方面存在一些问题。
建议学生在下次作业前加强词汇记忆，并在口语练习中多与同学交流、互相帮助。
同时，老师也会根据学生作业中出现的问题，调整教学内容和方法，以提高教学效果。
Lesson 1 Choosing a FlatPeriod 1Teaching Aims1．Review the Comparatives and Superlatives of adjectives and adverbs.2．Talk about flats.3．Learn the new modal verb.Difficult Points and Important PointsUnderstand and use “should” according to different context correctly. Teaching AidsText book, students’ book, a recorder and a computerTeaching ProcedureHomework1．Copy the new words.2．Pair work with your partners to talk about your flat.3．Complete some exercises of the modal verbs.Lesson 1 Choosing a FlatPeriod 2Teaching Objectives1．Learn the text by heart.2．Ask for and express opinions.3．Express agreement.Teaching DifficultiesMake comments by asking for and expressing one’s opinions. Teaching AidsText book, students’ book, a recorder and a computer Teaching ProcedureHomework1．Recite the text and role-play it.2．Talk about flats by asking for and expressing opinions.Lesson 1 Choosing a FlatPeriod 3Teaching Objectives1．Learn the reading by heart.2．Review the use of modal verb: should3．Talk about flats.Teaching DifficultiesExchange ideas by useful sentences.Teaching AidsText book, students’ book, a recorder and a computer Teaching ProcedureHomework1．Recite the reading.2．Write five to eight sentences to describe your flat.Lesson 2 New Housing EstatesPeriod 1Teaching Aims1．Tell the locations correctly.2．Describe a residential area by its locations and facilities.3．Compare housing estates in the past and the present. Difficult Points and Important PointsFind out the usage of “used to”.Teaching AidsText book, students’ book, a recorder and a computer Teaching ProceduresHomework1．Remember the new words and phrases.2．Pair work with your partners to describe your residential area.3．Do some practices with “used to”.Lesson 2 New Housing EstatesPeriod 2Teaching Aims1．Learn the text by heart.2．Have a command of “used to”.3．Compare housing estates in the past and the present. Difficult Points and Important PointsFind out the usage of “used to”.Teaching AidsText book, students’ book, a recorder and a computer Teaching ProceduresHomework1．Recite the text and role-play it.2．Practice the usage of “used to”.Lesson 2 New Housing EstatesPeriod 3Teaching Aims1．Learn the reading by heart.2．Review the usage of “used to”.3．Compare housing estates in the past and the present. Difficult Points and Important PointsCompare housing estates in the past and the present. Teaching AidsText book, students’ book, a recorder and a computerTeaching ProcedureHomework1．Recite the reading.2．Write five to eight sentences about your housing estate. Use the question cues.Lesson 3 Making Our Home GreenerTeaching Aims1．Get the main idea of the text through listening and exercises2．Learn and use some key words and expressions: make sth. +adj., look after, join, set out3．Talk about the benefits of trees, enhance the students’ consciousness of protecting environmentImportant PointsLearn and use the key words and expressionsDifficult PointsGet the main idea of the text through listeningTalk about the benefits of treesTeaching AidsMultimedia, Tape-recorder, Student's book 7A, WorksheetsTeaching ProcedureLesson 1 National Holidays第一课时【教学目标】1．了解我们国家的节日。
《Colours》作业设计方案（第一课时）一、作业目标本次作业旨在帮助学生巩固颜色词汇，提高英语听说能力，同时培养他们用英语表达事物的兴趣和自信心。
二、作业内容1. 词汇练习：学生需在课后复习颜色词汇，包括红色（red）、蓝色（blue）、绿色（green）、黄色（yellow）、黑色（black）、白色（white）和棕色（brown）。
要求他们能够熟练运用这些词汇进行简单的对话和描述。
2. 听说训练：学生需完成一套颜色相关的听说练习题，包括听录音并选择正确答案，看图片并描述颜色等。
这有助于提高学生的听力理解和口语表达能力。
3. 创意作业：学生需用英语描述一种他们最喜欢的颜色和与之相关的物品或场景。
这有助于培养他们的想象力，提高英语写作能力。
三、作业要求1. 独立完成：学生需独立完成作业，不得抄袭或他人协助。
2. 按时提交：学生需在规定时间内提交作业，逾期不候。
3. 认真对待：学生应认真对待作业中的每一道题目，确保答题的准确性和完整性。
四、作业评价1. 批改方式：教师将对提交的作业进行批改，给出分数和评语。
2. 评价标准：作业的完成情况、词汇运用、听力理解、口语表达和写作能力等都是评价的重要指标。
3. 反馈指导：对于普遍存在的问题，教师将在课堂上进行讲解和指导。
对于个别学生的问题，将给予单独的反馈和建议。
五、作业反馈1. 学生应认真阅读批改后的作业，并根据教师的反馈进行改进和提高。
2. 对于未能按时提交作业的学生，教师应及时提醒，并记录在案。
对于多次提醒后仍不按时提交的学生，将给予相应的纪律处分。
3. 对于在创意作业中表现出色或进步较大的学生，教师应给予表扬和鼓励，以激发他们的学习热情和自信心。
通过本次《Colours》课程作业，学生将能够进一步巩固颜色词汇，提高听说能力，并尝试用英语表达自己的喜好和感受。
同时，教师也将根据学生的完成情况和反馈，及时调整教学策略，以提高教学效果。
作业设计方案（第二课时）一、作业目标通过第二课时的作业，学生将进一步巩固和运用与颜色相关的词汇和表达，提高英语听说能力，培养英语学习的兴趣和自信心。
《Colours》作业设计方案（第一课时）一、作业目标本节课的作业旨在帮助学生进一步理解和掌握颜色词汇，同时通过实践和应用，提高他们的英语表达和沟通能力。
具体目标包括：1. 熟练掌握红色、蓝色、绿色、黄色等基本颜色词汇；2. 能够用英语描述物品的颜色；3. 培养用英语进行思维和表达的能力。
二、作业内容1. 词汇练习：学生需在课后抄写并记忆颜色词汇，包括红色、蓝色、绿色、黄色、白色、黑色、棕色等。
同时，完成一张包含这些词汇的填空练习题和选择题试卷。
2. 造句练习：学生需用所学颜色词汇造句，例如，“我的书包是蓝色的”，“他的足球是绿色的”等。
学生可以自由发挥，但要求语法正确。
3. 颜色配对：学生需完成一份颜色配对卡片，每张卡片上有两种不同的物品，需要学生用英语描述出它们各自的颜色，以便进行配对。
4. 故事编写：学生需根据所学颜色词汇，编写一个简单的英语小故事，故事中需要用到这些词汇。
这有助于培养学生的英语思维能力和表达能力。
三、作业要求1. 独立完成作业：要求学生独立完成所有作业内容，培养他们的独立思考能力；2. 认真对待作业：作业是巩固和检验学生学习成果的重要手段，学生应认真对待；3. 按时提交作业：学生需按照规定的时间及时提交作业，以便教师及时评价。
四、作业评价教师将根据学生提交的作业情况，进行评分和反馈。
对于完成出色的学生，将给予相应的奖励，以激励他们更好地学习英语。
评价标准包括词汇掌握情况、造句准确性、颜色配对完成情况以及故事编写创意性。
五、作业反馈对于作业中出现的问题和错误，教师将在课堂上进行讲解和纠正，以确保学生正确理解和掌握所学知识。
同时，教师也会根据学生的作业反馈，及时调整教学策略和方法，以提高教学效果。
通过本次作业，学生可以进一步巩固和拓展颜色词汇的学习，提高英语表达和沟通能力。
同时，通过完成作业，学生可以培养良好的学习习惯和思维方式，为将来的英语学习打下坚实的基础。
作业设计方案（第二课时）一、作业目标1. 复习和巩固学生对颜色的认知和表达，提高英语口语表达能力。
书籍设计作业配色方案在书籍设计中，配色方案是十分重要的一部分，它可以帮助读者更好地理解书籍内容，增加视觉的吸引力，并与书籍的主题和风格相匹配。
下面我将介绍几种常见的书籍设计配色方案。
1. 经典配色方案：这是一种常见的书籍设计配色方案，通常以黑白灰为基调，简洁而优雅。
这种配色方案适用于正式的书籍，如学术论文、法律文件等。
黑白灰的搭配一直都是一种经典色彩组合，给人一种稳重和专业的感觉。
2. 复古配色方案：这种配色方案通常使用柔和的暖色调，如棕色、青铜色和红褐色等。
这种配色方案可以给人一种怀旧和复古的感觉，适合用于设计艺术类书籍，如古典文学作品或历史相关的书籍。
3. 温暖配色方案：这种配色方案以温暖的颜色为主，如橙色、黄色和红色等。
这种色彩组合可以给人一种热情和活力的感觉，适用于教育类书籍或鼓励读者的开发个人潜力的书籍。
4. 冷色调配色方案：这种配色方案以冷色调为主，如蓝色、绿色和紫色等。
这种色彩组合可以给人一种冷静和平静的感觉，适合用于科技类书籍或冷静思考的主题。
5. 对比色配色方案：这种配色方案选择截然不同的颜色进行搭配，如黑白、红蓝等。
这种对比色的组合可以营造出强烈的视觉冲击力，使书籍设计更具吸引力。
6. 简约配色方案：这种配色方案以简洁和纯净为主，通常使用白色或淡灰色作为背景色，配以单一或少量的饱和度较高的颜色。
这种配色方案适合于现代设计风格的书籍，能够给人一种清晰和整洁的感觉。
在选择配色方案时，设计师应该考虑到书籍的主题、目标读者群体以及所要传达的情感和氛围。
同时，也需要注意避免过于花哨或过于暗沉的颜色搭配，以免影响读者的阅读体验。
总的来说，配色方案在书籍设计中起到了至关重要的作用，它可以通过色彩的组合来营造出适合书籍内容的氛围和情感。
一个恰当的配色方案可以提高书籍的吸引力，帮助读者更好地理解和欣赏书籍内容。
新视野大学英语4听说教程答案Unit OneWarming UpF T NGListeningUnderstanding Short Conversations1~5 A C B B D6~10 B A C C DUnderstanding a Long Conversation1~5 A B A C BUnderstanding a Passage1~5 A A D B CUndenstanding a Radio Program1 married in ST.Paul’s Cathedral2 was a guest at the wedding ceremory3 wore a hat with flowers at the wedding4 is remmembered as having been naughty5 was one of the designers of the wedding dressCulture TalkT F F TListening and Speaking1 They have high status.2 They get the attentions of the public.3 Using their fame to make money.HomeworkSupplementary ListeningTask 11~5 D A B B ATask 21~5 C A B B ATask 31、shortage2、assigned3、centered4、hospitallization5、treatment6、colleague7、decentialized8、There’re nurse-managers instead of head-nurses9、decidea among themselves who will work what to do and when10、an equal with other wise presidents of the hospitalUnit TwoWarming Up1、Her new book2、Original3、Use your own words to complete it,this question has no correct answers. ListeningUnderstanding Short Conversations1~5 D D D C B6~10 A A B C DUnderstanding a Long Conversation1~5 D A B B AUnderstanding a Passage1~5 B C D A CUndenstanding a Radio Program1 C2 A3 A4 C5 DCulture TalkF F T TListening and Speaking1(The Left Answer) It makes their point and makes you happy.2(The Right Answer) It is difficult to do.3(The Right Answer) Sometimes it’s dangerous.HomeworkSupplementary ListeningTask 11~5 D A B B ATask 21~5 B D A C ATask 31、sketch2、shadow3、paintings4、abroad5、Europe6、jewels7、exqute8、pictures of rooms with handsome dressed people in them9、not only the clothes and the lines of their faces10、but he was far greater than he would ever becomeUnit ThreeWarming Up1、god of mercy2、money,strength and health3、lucky onesListeningUnderstanding Short Conversations1~5 C D C B B6~10 B A C A BUnderstanding a Long Conversation1~5 A B D C BUnderstanding a Passage1~5 A B D B CUndenstanding a Radio Program1 An Australian scientist who won the Nobel Prize.2 The mysterious field of infectious diseases.3 By accident.4 It was probably extremely significant.5 He couldn't handle all that.Culture TalkT F T TListening and Speaking1 The poor trend to be angry easily and it will fanilly make a civil war.2 It can control the rate og crimes3 It can increase the econimicsHomeworkSupplementary ListeningTask 11~5 B C A D CTask 21~5 B A C B CTask 31、September2、retire3、retirement4、reduction5、practical6、pensions7、leisure8、The club arranges discussion groups and handicraft sessions9、a member can attend any course held there free of charge10、the financial section on Mondays and Wednesdays between six and eight p.m.Unit FourWarming Up1、Xerox’s Palo Alto Re search Center2、Verizon3、AmazonListeningUnderstanding Short Conversations1~5 B A D D A6~10 D C C A AUnderstanding a Long Conversation1~5 C B B B CUnderstanding a Passage1~5 A C B A CUndenstanding a Radio Program1 became Bill Gates' greatest contribution2 makes use of Gates' system3 was the plaything of nerds4 became a business tool5 made it a wish to dominate like Bill Gates6 was not fit to comment on upcoming innovationCulture TalkT T F FListening and Speaking1(The Left Answer) It provides a lot of information.2(The Right Answer) Some of the information is very dangerous.3(The Right Answer) Some of the information is not accurate.HomeworkSupplementary ListeningTask 11~5 B A B C ATask 21~5 A A B B ATask 31、fundamental2、dramatically3、majority4、workplace5、self-employed6、breadth7、notions8、its applications in personal computers, digital communications, and factory robots9、still unimagined technology could produce a similar wave of dramatic changes10、will have the greatest advantage and produce the most wealthUnit FiveWarming UpF NG TListeningUnderstanding Short Conversations1~5 A D D D B6~10 C D C A DUnderstanding a Long Conversation1~5 B B A C CUnderstanding a Passage1~5 D A B B AUndenstanding a Radio Program1 the perfect man checklists2 what the perfect man looks like3 much younger for yourself4 to develop your perfect man checklist5 burning the perfect man checklistCulture Talk1 Korean2 HongKong3 England4 USAListening and Speaking1 It can cause one to be dependent.2 It’s a nuisance.3 It will limit your freedom.HomeworkSupplementary ListeningTask 11~5 C D A B DTask 21~5 A C A C DTask 31、emerging2、residents3、participants4、companionship5、soldiers6、isolate7、extraordinary8、who happened to live by themselves die at twice the rate of those live with others9、It’s clear that reaching out to other can have our body strong10、Only 5 percent of U.S. consisted of the person living alone.Unit SixWarming Up1 Whether the man should return to society.2 15 years.3 Use your own words to complete it,this question has no correct answers. ListeningUnderstanding Short Conversations1~5 C B C D B6~10 C A D D BUnderstanding a Long Conversation1~5 A B C C DUnderstanding a Passage1~5 C D D A BUndenstanding a Radio Program1 Centennial Olympic Park2 North Cardwell,New Jersey3 Oklahoma City,Oklahoma4 the FBI laboratories5 ground zero6 an Atlanta abortion clinicCulture Talk1 USA2 Germany3 Singapore4 CanadaListening and Speaking1(The Left Answer) Punishing the criminals will deter others.2(The Right Answer) It is good for society.3(The Right Answer) It has no victims.HomeworkSupplementary ListeningTask 11~5 D C B A ATask 21~5 C B B A DTask 31、impeach2、scandal3、gambling4、Representatives5、accusations6、procedures7、opposition8、resigned as secretary of social welfare and urged the president to resign9、five economic advices to the President have resigned10、some committees in the House of RepresentativesUnit SevenWarming UpT F NGListeningUnderstanding Short Conversations1~5 B C A A D6~10 C B D A BUnderstanding a Long ConversationUnderstanding a Passage1~5 C C D B BUndenstanding a Radio Program1 shows God’s part in creating the universe.2 shows the existence of a man thousands of years ago.3 shows messages inscribed in DNA.4 shows a court opinion against Intelligent Design.5 shows God’s existence.Culture TalkT T F FListening and Speaking1 Groups are similar biologically except for skin color.2 Groups have different culture3 Groups provide something unique.HomeworkSupplementary ListeningTask 11~5 D D A B BTask 21~5 A C B A DTask 31、would-be2、intelligence3、genes4、athletic5、medical6、disclosed7、consideration8、the sum American egg donors expect to be paid9、plus all the costs of medical treatment and insurance10、almost half the cost of fees for the students’ four-year college course.Unit EightWarming Up1 going to quit2 work harder3 majority raceListeningUnderstanding Short Conversations1~5 C A A B C6~10 D D A C BUnderstanding a Long ConversationUnderstanding a Passage1~5 D A B B AUndenstanding a Radio Program1 Bill Gates2 Warren Buffet3 KP Singh4 Martha Stewart5 Ronald Lauder6 Louisa KrollCulture Talk1 Japan2 UK3 America4 Hong Kong Listening and Speaking1 Society should be fair.2 Women should enjoy representation.3 It makes leaders help to do something for women.HomeworkSupplementary ListeningTask 11~5 A C D B CTask 21~5 A D B B BTask 31、greeted2、freshman3、spite4、fluke5、agitated6、faculty7、particularly8、I had the highest average in the freshman class9、Then, she took out a copy of the examination paper10、I was so angry that I started punding herUnit NineWarming Up1 Whether it’s Chinese enough to appeal to Chinese people2 American culture3 Use your own words to complete it,this question has no correct answersListeningUnderstanding Short Conversations1~5 A C B D C6~10 D A A B CUnderstanding a Long Conversation1~5 D A B B AUnderstanding a Passage1~5 D B B C CUndenstanding a Radio Program1 His brother’s two daughters.2 They drove there.3 Children under three.4 They watched the parade.5 He sat down and had a rest for a few minutes.Culture TalkT T F TListening and Speaking1 Fantastic rides.2 So much to see.3 Great memories never to forget.HomeworkSupplementary ListeningTask 11~5 C B A C DTask 21~5 B A D C BTask 31、Authorities2、grant3、opera4、not traditional5、staged6、journolists7、tunnel8、Great performer is special for new introduction of the story9、who kills all suitors who can answer her three riddles10、Some Chinese audience complain that the princess has none of the grace of a true Chinese ladyUnit TenWarming UpNG T FListeningUnderstanding Short Conversations1~5 D B A C B6~10 B B C B AUnderstanding a Long Conversation1~5 D B C A BUnderstanding a Passage1~5 C B D D AUndenstanding a Radio Program1 is something not known for sure2 is trying to figure out how dreams help in solving problems3 is something everyone should do4 is important in interpreting dreams5 is something a person might be afraid ofCulture TalkT T F TListening and Speaking1 It causes stress.2 What area you may develop.3 High score can bring you confidence.HomeworkSupplementary ListeningTask 11~5 C D C A ATask 21~5 A D C B ATask 31、rarely2、consulting3、renting4、agent5、appointment6、exchange7、praises8、the people who work there actually know where things are and they'll take you right to them9、I will tell you what I really like about Publix10、There's a different grocery store near my house, but all that the employees do there is to grunt。
《Colours》作业设计方案（第一课时）一、作业目标本作业旨在巩固学生在第一课时中学习的颜色类英语单词，包括基础颜色的认识与发音。
通过实际操作，学生能够正确运用所学颜色词汇进行简单描述，并能够结合实际生活情境进行应用。
二、作业内容作业内容主要包括三个方面：单词记忆、颜色配对练习和创作彩色画作。
1. 单词记忆：学生需复习并熟记至少十个基础颜色类英语单词，如red（红）、blue（蓝）、green（绿）等，并能够准确发音。
2. 颜色配对练习：学生需使用颜色卡片或实物进行颜色配对游戏。
每张卡片或实物上印有不同颜色的图案，学生需根据图案的颜色找到对应的英文单词卡片。
此项练习旨在加深学生对颜色类英语单词的理解与记忆。
3. 创作彩色画作：学生选择自己喜欢的颜色，创作一幅简单的彩色画作。
在创作过程中，学生需使用所学颜色类英语单词描述画作中的颜色，如“I used red for the sun”等。
画作完成后，学生需将作品拍照或手绘在作业本上，并在旁边用英文标注出所用颜色的名称。
三、作业要求1. 单词记忆要求准确无误地记住至少十个基础颜色类英语单词的拼写与发音。
2. 颜色配对练习要求学生在规定时间内完成尽可能多的配对，并准确说出每个颜色的英文单词。
3. 创作彩色画作要求画面简洁明了，色彩搭配合理，能够准确使用所学颜色类英语单词描述画作中的颜色。
画作应体现出学生的创意与想象力。
四、作业评价1. 评价标准：根据学生完成作业的准确性、速度和创意进行评价。
单词记忆和颜色配对练习的准确性为主要评价标准；创作彩色画作的创意和色彩搭配为次要评价标准。
2. 评价方式：教师批改作业时，需对学生的单词记忆和颜色配对练习的准确性进行核对；对彩色画作进行整体评价，给出鼓励性的评价意见和建议。
五、作业反馈1. 对于学生在作业中出现的错误，教师需在批改时进行纠正，并给出正确的答案或解释。
2. 对于表现优秀的学生，教师应给予表扬和鼓励，激发学生的学习积极性。
《Colours》作业设计方案（第一课时）一、作业目标本次作业旨在帮助学生巩固颜色词汇，提高英语听说能力，同时培养他们用英语表达事物的兴趣。
二、作业内容1. 词汇练习：学生需复习并默写颜色词汇，包括红色（red）、蓝色（blue）、绿色（green）、黄色（yellow）、黑色（black）、白色（white）和棕色（brown）。
2. 听说练习：学生需在家中观看一段关于颜色的英语动画视频，并尝试用英语描述视频中的场景和角色。
3. 创意作业：学生需选择一种他们喜欢的颜色，用英语描述一种由这种颜色构成的事物或场景。
例如，可以选择红色作为主色，描述一个充满红色的苹果、草莓或火龙果的场景。
三、作业要求1. 完成词汇练习后，学生需家长签字确认。
2. 观看动画视频后，学生需家长提供视频截图或描述，以便教师了解学生的完成情况。
3. 创意作业需用英语书写，字迹工整，尽量做到语言流畅、逻辑清晰。
4. 完成上的作业后，请将作业提交至教师指定的平台。
四、作业评价1. 教师将根据学生的词汇默写情况、观看视频后的反馈以及创意作业的完成质量，给予学生相应的评价和反馈。
2. 评价将以分数或等级形式呈现，同时指出学生在作业中存在的问题和改进建议。
五、作业反馈1. 学生将收到教师关于作业的评价和反馈，以便了解自己的完成情况及需要改进的地方。
2. 学生可向教师提问或寻求帮助，教师将尽力提供解答和建议。
通过本次作业，学生将进一步巩固颜色词汇，提高英语听说能力，同时培养用英语表达事物的兴趣。
教师将根据学生的完成情况，调整教学策略，以满足学生的需求。
此外，教师还将鼓励学生互相交流、分享自己的创意作业，以激发他们的学习热情和创造力。
同时，教师也将关注学生在实际生活中运用英语的能力，以便更好地评估教学效果。
总之，本次小学英语课程《Colours》作业设计方案旨在通过多元化的作业形式，帮助学生巩固颜色词汇，提高听说能力，并培养他们用英语表达事物的兴趣。
(1)
(a) What are some properties common to most ceramic materials?
(b) Define coordination number and critical radius ratio for the packing of ions in ionic solids.
Solution:
(a) Common properties of most ceramic materials:
hard and brittle, low toughness and ductility, good electrical and thermal insulators, high melting temperatures, high chemical stability.
(b)
Coordination number: the number of equidistant (等距离的) nearest neighbors to an atom or ion in a unit cell of a crystal structure.
Critical radius ratio: the ratio of the central cation of that of the surrounding anions when all the surrounding anions just touch each other and the central cation.
(2)
The zinc blende crystal structure is one that may be generated from close-packed planes of anions.
(a) Will the stacking sequence for this structure be FCC or HCP? Why?
(b) Will cations fill tetrahedral or octahedral positions? Why?
(c) What fraction of the positions will be occupied?
Solution:
(a) The stacking sequence of close-packed planes of anions for the zinc blende crystal structure will be the same as FCC (and not HCP) because the anion packing is FCC.
(b) The cations will fill tetrahedral positions since the coordination number for cations is four.
(c) Only one-half of the tetrahedral positions will be occupied because there are two tetrahedral sites per anion, and yet only one cation per anion.
(3)
On the basis of crystal structure, compute the theoretical density for sodium chloride. Ionic radii are Na+ = 0.102 nm and Cl- = 0.181 nm. Solution ：
For NaCl unit cell with FCC structure, the number of sodium and chloride ions is 4. Furthermore,
m Na = 22.99 g/mol
m Cl = 35.45 g/mol
The lattice constant of the NaCl unit cell:
2()2(0.1020.181)0.566Na Cl a r r nm nm nm +-=+=⨯+=
The volume of the NaCl unit cell is
33223(0.566) 1.8110V a nm cm -===⨯
The density of NaCl is
3232234()4(22.9935.45)/ 2.14/6.0210/ 1.8110Na Cl m m m g mol g cm V V atom mol cm
ρ-+⨯+====⨯⨯⨯
(4)
A reaction-bonded silicon nitride ceramic has a strength of 300 MPa and a fracture toughness of 3.6
What is the largest-size internal crack that this material can support without fracturing? Use Y=1 in the fracture-toughness equation.
Solution:
300f MPa σ=
, 3.6IC K =1Y =
According to IC f K Y σ=
So 2
2522(3.6 4.581045.8(300)
IC f K a m m MPa μπσπ-===⨯= Thus, the largest internal crack is
2245.891.6a m m μμ=⨯=
(5)
(a) What are the three main components of a traditional ceramics?
(b) What role does each component play in the forming and firing procedures?
Solution:
(a) Three main components: clay, silica, feldspar.
(b) Clay provides workability of the traditional ceramics before firing
hardens it and constitutes the major body material. Silica is the refractory component. Feldspar bonds the refractory components together.
(6)
(a) Define the glass transition temperature.
(b) Name two glass-forming oxides. What are their fundamental subunits and their shape?
Solution:
(a) Glass transition temperature: the center of the temperature range in which a noncrystalline solid changes from being glass-brittle to being viscous.
(b)
SiO2: SiO44- , tetrahedron.
B2O3: BO33-, triangle; or BO44-, tetrahedron.。
