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研究生学术英语答案Unit 4
Section A
பைடு நூலகம்Part 1 Lead-in
Best Film Editing Best Picture Best Writing, Screenplay Based on Material from Another Medium Nominated • Oscar: Best Actor in a Supporting Role Best Cinematography
Introduction to Cartoon Films (2)
Unit 4 Forrest Gump
Section A Focused Activities Part 1 Lead-in
Part 2 Watching & Listening
Part 3 Fun Time
Section A
Part 1 Lead-in
1. Which are the first lines of the film? A) Hello. I’m Forrest, Forrest Gump let me tell you my story. B) Hello. I’m Forrest Gump and this is Jenny, my Jenny. C) Hello. My name’s Forrest, Forrest Gump. You want a √ chocolate. D) Hello. Forrest Gump is my name and glad to meet you.
Section A
Part 2 Watching & Listening
√
√
4. How does Forrest get his name? A) He’s named after a Civil War hero. B) He’s named after his grandfather. C) He’s named after one of his relatives. D) He’s named after a famous general. 5. When Forrest’s mama says, “Life was like a box of chocolates. You never know what you’re gonna get”, she means that A) “Life is compared to a voyage.” B) “Life is but a hard and tortuous journey.” C) “Life is full of wonders for us to explore.” D) “Life is short for everyone.”
四的四字成语
四的四字成语关于四的四字成语导语：最美人间四月天里面说过，你是一树一树的花开，是燕在梁间呢喃，——你是爱，是暖，是希望，你是人间的四月天!关于四的成语也有很多的，请大家欣赏一下!1. 四海升平——指天下太平.2. 四海他人——指没有亲戚关系.3. 四海为家——原指帝王占有全国.后指什么地方都可以当作自己的家.指志在四方,不留恋家乡或个人小天地.4. 四海一家四海之内,犹如一家.形容天下一统.5. 四荒八极——四面八方极偏远之地.6. 四郊多垒——垒：营垒.敌军四面逼近,形势危急.也比喻竞争的对手多.7. 四角俱全——比喻完美无缺.8. 四脚朝天——四脚：指四肢.形容仰面跌倒.也形容人死去.9. 四马攒蹄——指两手两脚被捆在一起.10. 四面八方——指各个方面或各个地方.11. 四面出击——形容工作全面展开,没有重点.12. 四面楚歌——比喻陷入四面受敌、孤立无援的境地.13. 四面受敌——各个方面受到敌对势力的威胁或攻击.14. 四平八稳——原形容身体各部位匀称、结实.后常形容说话做事稳当.也形容做事只求不出差错,缺乏积极创新精神.15. 四清六活——形容机灵干练.16. 四衢八街——指大城市街道非常多.17. 四山五岳——泛指四面八方各个地区.18. 四时八节——四时：指春夏秋冬四季;八节：指立春、春分、立夏、夏至、立秋、秋分、立冬、冬至.泛指一年四季中各节气.19. 四时之气——本指一年四季的气象,后以“备四时之气”喻指人的.气度弘远.20. 四书五经——四书：亦称四子书,即《大学》、《中庸》、《论语》、《孟子》;五经：《诗》、《书》、《礼》、《易》、《春秋》.指儒家经典.21. 四体百骸——人体的各个部分.泛指全身.同“四肢百骸”.22. 四体不勤——四肢不劳动,形容脱离劳动.23. 四亭八当——亭、当：即停当,妥贴.形容一切事情都安排得十分妥贴.24. 四停八当——形容一切事情都安排得十分妥贴.同“四亭八当”.25. 四通八达——四面八方都有路可通.形容交通极便利.也形容通向各方.26. 四通五达——四通八达.形容交通畅达无阻.27. 四姻九戚——比喻亲戚极多.28. 四战之地——指四面平坦,无险可守,容易受攻击的地方.29. 四战之国——指四面平坦,无险可守,容易受攻击的地方.30. 四肢百骸——人体的各个部分.泛指全身.31. 四肢百体——人体的各个部分.泛指全身.同“四肢百骸”.32. 四至八道——旧时标志土地界域的用语.表示四面八方所到之处及通往的道路.33. 四百四病——指四肢百体的四时病痛.泛指各种疾病.34. 四不拗六——指少数人拗不过多数人的意见.35. 四冲八达——指四通八达的要道.同“四冲六达”.36. 四冲六达——指四通八达的要道.37. 四大皆空——四大：古印度称地、水、火风为“四大”.佛教用语.指世界上一切都是空虚的.是一种消极思想.38. 四方八面——到处;各个方面.39. 四方辐辏——比喻四方的人才或货物像车轮上的辐条聚集在毂上那样汇集到一处.后引申为从各方聚集的意思.40. 四方之志——志：志向.指远大的志向.亦作“志在四方”.41. 四分五裂——形容不完整,不集中,不团结,不统一.42. 四分五落——形容分散零乱.43. 四分五剖——四分五裂.形容分散,不统一.44. 四纷五落——形容分散零乱.同“四分五落”.45. 四海波静——比喻天下太平.46. 四海承风——指全国都接受教化.47. 四海鼎沸——四海：古人以为中国四境有海环绕,用以指全国各地;鼎沸：比喻局势不安定,如同鼎水沸腾.形容天下大乱.48. 四海九州——指全中国.49. 四海飘零——四海：代指全国各地.飘零：比喻遭到不幸,失去依靠,生活不安定.指到处飘泊,生活无着.50. 四海升平——升平：太平.天下太平.51. 巴三览四——比喻说话拉扯,没有中心.52. 不三不四——指不正派,也指不象样子.53. 差三错四——颠倒错乱.54. 倒三颠四——形容言行无条理或神智不清,精神恍惚.55. 低三下四——形容态度卑贱低下也指工作性质卑贱低下.56. 颠三倒四——形容说话做事错杂紊乱.57. 丢三落四——形容做事马虎粗心,不是丢了这个,就是忘了那个.58. 接三连四——接连不断.59. 拉三扯四——指谈话或议论牵扯无关的人或事.60. 拿三搬四——比喻不服从调派.61. 欺三瞒四——一再欺骗隐瞒.62. 说三道四——形容不负现任地胡乱议论.63. 挑三拣四——形容过分地挑剔.也指对工作或事物再三挑选.64. 调三窝四——搬弄是非,挑拔离间.65. 推三阻四——找各种借口推托.66. 言三语四——言、语：说、讲.形容人多嘴杂,议论纷纷.67. 再三再四——重复好几次.68. 张三李四——假设的名字,泛指某人或某些人.69. 朝三暮四——原指玩弄手法欺骗人.后用来比喻常常变卦,反复无常.。
模块4 餐饮产品的成本核算
一、餐饮成本月报表
（一）月餐饮成本核算的方法
2．“以存计耗”，倒求成本 原材料盘存表的格式见表4-5。
ቤተ መጻሕፍቲ ባይዱ
一、餐饮成本月报表
（二）餐饮成本月报表的编制
如表4-7所示，该企业的标准成本率为48％， 实际成本率为44.5％，比标准成本率低3.5 个百分点，说明该企业对餐饮成本控制有一 定的成效或者存在投料不足等问题，需要进 一步分析原因。
一、餐饮产品成本核算的方法
（二）先分后总法
餐饮业的成本计算，一般是根据所耗用的原材料每月计算一次。如果厨房领用的原材料当月完全用完无 剩余，则领用的原材料金额就是当月全部产品的成本；若有剩余原材料，则采用“以存计耗法”倒求成 本。
其计算公式为： 本月耗用原材料成本＝月初原材料结存额 + 本月领用原材料总额 - 月末原材料盘存额
一、面食产品成本核算的方法
【例4-2】某餐馆制作三鲜炒面，每份用料如下：鲜面条0.2千克，单价4元/千克；瘦肉0.05千克，单价 20元/千克；香菇0.02千克，单价12元/千克；胡萝卜0.02千克，单价3.6元/千克；韭菜0.02千克，单 价4.4元/千克；豆芽0.02千克，单价3.2元/千克；姜丝0.01千克，单价2.4元/千克；葱丝0.01千克，单 价2.20元/千克；生粉0.02千克，单价1.5元/千克；食用油0.07千克，单价25元/千克；盐、生抽、鸡精 等作价0.2元。试求每份三鲜炒面的成本是多少。
二、餐饮成本日报表
由于餐饮成本月报表报告间隔时间过长，对企业的日常业务指导意义不大，因而，企业除了进行月 餐饮产品成本核算外，还需要进行日餐饮产品成本核算。
餐饮企业每日的餐饮产品成本由直接购料和从仓库领料组成。直接购料的成本数据可从企业每天的 购料单上获得，从仓库领料的成本数据可从原材料领料单上得到。原材料领料单的格式如表4-8所示。
四的所有写法
四的所有写法
“四”有很多种写法，包括楷书、行书、草书、隶书、篆书等。
以下是一些示例：
1. 楷书：楷书是一种非常规整的字体，每个字都有自己的标准写法。
在楷书中，“四”的写法是：先写上面一横，再写中间两竖，最后写下面一横。
2. 行书：行书是一种相对楷书而言更为流畅的字体，常常用于书写行草书。
在行书中，“四”的写法与楷书类似，但是更为流畅自然。
3. 草书：草书是一种较为潦草的字体，常常用于快速书写。
在草书中，“四”的写法是：先写一横，再写两竖，最后写一横。
4. 隶书：隶书是一种较为庄重的字体，常常用于书写碑文等。
在隶书中，“四”的写法是：先写上面一横，再写中间两竖，最后写下面一横。
5. 篆书：篆书是一种较为古老的字体，常常用于书写古文等。
在篆书中，“四”的写法是：先写上面一横，再写中间两竖，最后写下面一横。
总之，“四”的写法有很多种，不同的字体有不同的写法。
以上只是列举了一些常见的写法，具体可以根据需要选择适合的字体进行书写。
营销学四大经典理论：4P、4C、4R、4l
营销学四⼤经典理论：4P、4C、4R、4l4P理论 即产品（product）、价格（price）、促销（promotion）、渠道（place）四要素 由密西根⼤学教授杰罗姆•麦卡锡（E.Jerome Mccarthy）1960年提出，“它的伟⼤在于它把营销简化并便于记忆和传播”。
产品包含核⼼产品、实体产品和延伸产品。
⼴义的产品可以是有形的实体，也可以是⽆形的服务、技术、知识或智慧等。
价格的制定⼿段很多，竞争⽐较法、成本加成法、⽬标利润法、市场空隙法，这些⽅法的⽬标是使产品成为可交换的商品。
企业以盈利为⽬标，所以定价要具有兼顾销售效率和企业效益的双重考虑，打价格战是⼀种定价和竞争策略，但价格低并⾮总是凑效，曾经就有⼀个朋友，⾯临⽟兰油的同⼀个产品在两个不同商家销售价格不同的购买选择，⼀家是按全价销售，另⼀个则是⼋折销售。
结果却是选择了原价购买。
信息不对称，使价格中蕴涵了太多的附加臆测信息，品质、期限、真伪、质量、效⽤，价格不仅与产品本⾝相关联，也与品牌的附加内涵和价值相关联，与市场的供求关系相关联，与所选择的购物场所的信誉相联系。
传统意义的促销是⼈员推⼴、⼴告、攻关活动和销售促进。
这些⽅式在营销过程中有着⾮常⼴泛的应⽤。
渠道是产品从⽣产⽅到消费者终端所经历的销售路径。
普通消费品会经过代理商、批发商、商场或零店的环节。
B2C模式中也有电话直销、电视直销、⽹络直销、⼈员直销、专卖店直销等模式。
直销模式⼤⼤缩减了从⼚家到买家的中间环节，将中间利润让渡给消费者或作为新的营销模式所产⽣的额外费⽤的补偿。
B2B模式中也可能采取⼚家对⼚家的直接销售或选取代理商的中间销售模式。
4P’s之后，因为服务业在70年代迅速发展，有学者⼜增加了第5个“P”，即“⼈”(People)；⼜因为包装在包装消费品营销中的重要意义，⽽使“包装”(Packaging)成为⼜⼀个“P”；70年代，“营销管理之⽗”科特勒在强调“⼤营销”的时候，⼜提出了两个“P”，即公共关系(Publications)和政治(Politics)。
4为什么是中国最吉利的数字
一．4为什么是中国最吉利的数字？
1、人丁兴旺：首先四就像是一个四合院，象征着家族中人丁兴旺、子孙满堂，这是一种非常有福气的寓意。
所以对于一个人丁稀少的家庭来说，最好选择和数字四有关的东西，比如住在4层楼，买东西买4个等等，这都是能够增加家里人口的好办法，而且让家中的子孙运会一直增长下去。
2、好事成双：数字四本身就是一个双数，所以大多数的时候，它们都是代表着成双成对的寓意，比如四喜临门、四喜发财等等，在民间还有一道菜叫做四喜丸子，这些说法都是在寓意着好事成双，象征着一种极为富贵吉利的寓意。
故而我们可以将数字四作为吉利数字来进行使用。
3、和谐稳固：自古以来，中国的建筑设计和园林风格都是在讲究对称的，因为人们相信四平八稳的对称才是最和谐、最稳固的形态，直到今天，方方正正依旧还是各种设计种主要的运用方式，比如衣柜、桌椅等等，都是在讲究方方正正的对称。
而数字四就是这样方方正正的对称，所以四代表着和谐和稳固。
4我喜欢的动植物
1．我最喜爱的一种小动物 kk狗成为人类的朋友已经有几千年的历史了，近年来随着人民生活水平的提高，城市居民养狗者大有人在。这也难怪，比起一些忘恩负义只认金钱不认友情的人，狗的忠诚可靠、舍身救主的侠义精神，真有天渊之别。人们爱狗，又总以为自己很了解狗，狗也很了解自己。几乎所有的养狗者都会夸耀自己的狗如何听话，如何懂事，然而，这些爱狗者，其实并没有懂得狗的语言。当狗看见你就将尾巴上翘并弯向背部时，大概大多数人都会认为这是在向自己表示友好和善意。其实，你错了，此时你的爱犬正想告诉你，它愿意不惜一切为你效劳。当狗看见你就将尾巴下垂并左右稍许晃动时，你一定以为他还是向你表示友好，你又错了。这时，它想告诉你的是，“我感觉不太舒服”。而当狗将尾巴左右大幅晃动时，它才确实一切都好，没有不舒服，只是想告诉你，它喜欢你。狗舔的动作不是来表达亲意的，而是想引起你对某些事的注意，比如它饿了，想吃些东西，这大致相当于人类婴儿的某种哭声。当一条生狗向你吼叫，有时它确实对你表示敌意或警惕之心，有的时候它不过是朝你笑呢，你大可不必害怕。据说，狗的智商远比人类想象的要高，能够理解人类的200多个单词和一些形体语言，相当于一个两岁婴儿的水平，人类固然不应对狗的智商期望过高，但也不应低估，而且更重要的是，人类也要学会理解狗的语言，不然不仅你不能满足爱狗需求，而且你的爱狗心中想的却是“我的主人真傻”。
上海外语教育出版社大学英语听说教程4听力原文
全新版大学英语听说教程第四册听力原文（上海外语教育出版社）Unit1(BOOK4)Part B The Hospital WindowJack and Ben, both seriously ill, occupied the same hospital room. Jack, whose bed was next to the room's only window, was allowed to sit up in his bed for an hour each afternoon to help drain the fluid from his lungs. But Ben had to spend all day and night flat on his bed. To kill time the two men began to talk. They talked for hours about their wives, families, their homes, their jobs, their involvement in the military service, and where they had been on vacation. As days went by, a deep friendship began to develop between them.Every afternoon when Jack could sit up, he would pass the time by describing to Ben all the things he could see outside the window. And Ben began to live for those one-hour periods where his world would be broadened and enlivened by all the activity and color of the world outside.The window overlooked a park with a lovely lake. Ducks and swans played on the water while children sailed their model boats. Young lovers walked arm in arm amid flowers of every color of the rainbow. Grand old trees beautified the landscape, and a fine view of the city skyline could be seen in the distance.As Jack described all this in exquisite detail, Ben would close his eyes and imagine the picturesque scenes.One warm afternoon Jack described a parade passing by. Although Ben couldn't hear the band -- he could see it in his mind's eye as Jack portrayed it with descriptive words.Days and weeks passed. One morning the day nurse arrived to bring water for their baths only to find the lifeless body of Jack, who had died peacefully in his sleep. She was saddened and called the hospital attendants to take the body away.Ben was heart broken. Life without Jack was even more unbearable. How he longed to hear Jack's voice and his melodious descriptions of the outside world! As he looked at the window, an idea suddenly occurred to him. Perhaps he could see for himself what it was like outside. As soon as it seemed appropriate, Ben asked if he could be moved next to the window. The nurse was happy to make the switch, and after making sure he was comfortable, she left him alone.Slowly, painfully, he propped himself up on one elbow to take his first look at the world outside. Finally, he would have the joy of seeing it for himself! He strained to slowly turn to look out the window beside the bed. It faced a blank wall!'What could have compelled my roommate to describe such wonderful things outside this window?' Ben asked the nurse when she returned.'Perhaps he just wanted to encourage you to live on,' she said. 'You know, he was blind and could not even see the wall.'Questions:1. What does the story mainly tell us?2. Which of the following adjectives can best describe Jack?3. What did Jack describe to Ben according to the story?Part CAdditional ListeningShort ConversationsConversation 1:M: How do you like your roommate, Debby?W: Ever since we met on the first day of college, we've been inseparable.Q: What do you know about Debby and her roommate?Conversation 2:M: Have you heard from Linda lately? You two were so intimate in college.W: Well, honestly, I haven't heard from her as much as I used to since she moved to the east coast two months ago. But I'm sure the friendship between us is as strong as it was before.Q: What can you infer from the woman’s response?Conversation 3:W: Do you keep in touch with your old friends back home now that you don't see them regularly? M: Frankly, after I moved to this city, I'm out of touch with most of them except a few close ones. Q: What does the man mean?Conversation 4:W: It's polite to call a friend before we visit, isn't it?M: You're right. People usually don't like surprise visits. But close friends often drop in on each other.Q: What does the man mean?Conversation 5:M: Cathy, it seems that you and Sally do almost everything together.W: That's true. You see, we were born on the same day. We both majored in fashion designing. And we even have the same love for using bright-colored material in our designs. Isn't it amazing! Q: What can we learn from the conversation?Part DThe Colors of FriendshipLegend has it that the colors of the world started to quarrel one day. All claimed that they were the best, the most beautiful.Green said: "Clearly I am the most important. I am the sign of life and of hope. I was chosen for grass, trees and leaves. Without me, all animals would die."Blue interrupted: "You only think about the earth, but have you ever considered the color of the sky and the sea?"Hearing this, Yellow chuckled: "You are all so serious. I bring laughter, gaiety and warmth into the world. I am the color of the sun, the moon and all the stars. Without me there would be no fun."Orange started next to blow her trumpet: "I am the color of health and strength. I may be scarce, but I am precious, for I serve the needs of human life."At this, Red could stand it no longer. He shouted: "I am the ruler of all of you. I am the color of blood -- life's blood! I am also the color of danger and bravery, of passion and love."Purple rose up to his full height: "I am the color of royalty and power. I am the sign of authority and wisdom. People do not question me! They listen and obey."Finally Indigo spoke: "Think of me. I am the color of silence. You hardly notice me, but without me you all become superficial. I represent thought and reflection."And so the colors went on boasting. Their quarrelling became louder and louder. Suddenly there was a startling flash of bright lightning, followed by a roll of thunder. Rain started to pourdown. The colors crouched down in fear, drawing close to one another for comfort.Just then rain began to speak: "You foolish colors, fighting amongst yourselves, each trying to dominate the rest. Don't you know that you were each made for a special purpose, unique and different? Join hands with one another and come to me."Doing as they were told, the colors united and joined hands.Then rain continued: "From now on, when it rains, each of you will stretch across the sky to form a great bow of colors as a reminder that you can all live in peace. The rainbow is a sign of hope for tomorrow."And so, whenever a good rain washes the world, a rainbow appears in the sky, to let us remember to appreciate one another.Unit 2Part BEmbarrassing Experiences (Part One)Interviewer: Rob, you went to Brazil, didn't you?Rob: Yes, I did.Interviewer: So, what happened?Rob: Well, I went into this meeting and there were about, er... seven or eight people in there and I just said 'Hello' to everybody and sat down. Apparently, what I should have done is to go round the room shaking hands with everyone individually. Well, you know, it's silly of me because I found out later it upset everyone. I mean, I think they felt I was taking them for granted.Kate: Well, I know that because when I was in France the first time, I finished a meeting , with 'Goodbye, everyone!' to all the people in the room. There were about half a dozen people there but I was in a hurry to leave, so I just said that and left. Well, I later found out that what I should have done is shake hands with everyone in the group before leaving. Now, apparently, it's the polite thing to do.Interviewer: Well, people shake hands in different ways, don't they?Rob: Oh, yes, that's right, they do. See, normally I shake hands quite gently when I meet someone. So when I went to the US for the first time, I think people there thought my weak handshake was a sign of weakness. Apparently, people there tend to shake hands quite firmly.Kate: Oh, gosh, you know, that reminds me: on my first trip to Germany, it was a long time ago, I was introduced to the boss in the company when he passed us in the corridor. Well, I wasn't prepared, and I mean, I had my left hand in my pocket. And when we shook hands I realized my left hand was still in my pocket. Well, that was, you know, very bad manners and I was quite embarrassed.Interviewer: And how about using first names? Have you made any mistakes there?Rob: Oh, yes, I have! When I first went to Italy I thought it was OK to use everyone's first name so as to seem friendly. And I later discovered that in business you shouldn't use someone's first name unless you are invited to. Oh, and you should always use their title as well.Kate: Hm, yeah, well, when I met people in Russia, you know, they seemed to be puzzled when I shook hands with them and said 'How do you do?' Well, what they do when they greet a stranger is to say their own names, so I had that all wrong!Rob: Oh, yes, I agree with that. Remembering names is very important.Interviewer: Shall we take a break? When we come back we'll move on to our next topic.Kate & Rob: OK.Questions:1. What is the conversation mainly about?2. Who might be the people Rob and Kate met in various countries?3. What can we infer about Kate and Rob from the conversation?4. Which countries has Kate visited, according to the conversation?5. Which countries has Rob visited, according to the conversation?6. What is the main message that the speakers want to tell us?Part CAdditional ListeningAmerican PartiesAs you would imagine, Americans move about a great deal at parties. At small gatherings they may sit down, but as soon as there are more people than chairs in a room - a little before this point - you will see first one and then another make some excuse to get to his feet to fetch a drink or greet a friend or open a window until soon everyone is standing, moving around, chatting with one group and then another. Sitting becomes static beyond a certain point. We expect people to move about and be "self-starters". It is quite normal for Americans to introduce themselves; they will drift around a room , stopping to talk wherever they like, introducing themselves and their companions. If this happens, you are expected to reply by giving your name and introducing the person with you; then at least the men generally shake hands. Sometimes the women do so as well, but often they merely nod and smile. A man usually shakes a woman's hand only if she extends it. Otherwise he too just nods and greets her.Statements:1. We can't imagine that Americans do not like big parties and they prefer going around at parties.2. At small parties they may sit down, but as more people come, they would stand up and move about.3. The reason why Americans like to stand is that they like the free atmosphere of the party.4. The meaning of "self-starters" is that Americans help themselves to drinks during the parties.5. Americans are more open-minded than British people according to the passage.6. If a woman doesn't extend her hand to a man at the party, he should not shakes hands with the woman.7. The passage shows a unique aspect of American culture.Embarrassing Experiences (Part Two)Interviewer: Let's go on with our talk. What do you think of business cards, Rob?Rob: I found them very useful when I was in Japan not so long ago. Each person can clearly see the other's name and the job title on the card. And I found out that you have to treat business cards with respect. What you've got to do is hold them with both hands and then read them very carefully. What happened to me was the first time I just took a man's card with one hand and put it straight into my pocket.Interviewer: What other advice do you have, Kate?Kate: Well, one time I unintentionally caused some problems when I was in China. Well, I was trying to make a joke when I pretended to criticize my business associate for being late for a meeting. And he was embarrassed, I mean, he was really embarrassed instead of being amused. Now you shouldn't criticize people in China or embarrass them. I mean, you must avoid confrontation. That's for sure!Rob: Oh, I must tell you about the first time I was in Mexico! I have to admit I found it a bit strange when business associates there touched me on the arm and the shoulder. Well, I tried to move away and, of course, they thought I was being very, very unfriendly. Apparently, it's quite usual there for men to touch each other in, you know, in a friendly way. Oh ... oh, and another thing, the first time I went to Korea I thought it was polite not to look someone in the eye too much. The Koreans I met seemed to be staring at me when I spoke, which seemed, you know, a bit odd at first. In Korea, eye contact conveys sincerity and it shows you're paying attention to the speaker.Kate: Oh, well, it seemed strange because you British don't look at each other so much when you're talking to each other. I mean, you look away, you know, most of the time. I found this hard to deal with when I first came to the UK, because people seemed to be embarrassed when I looked at them while they were speaking to me.Interviewer: So what's the thing visitors to Britain should avoid most?Rob: Well, I don't think we're all that sensitive, do you, Kate?Kate: Ohoo, well, I'll tell you, I made a big mistake when I was in Scotland. I found myself referring to the UK as "England" and to the British as "the English". Now, I know that would be just as bad in Wales, I guess.Rob: Yes, it certainly would!Unit 3Part BBirthday Celebrations Around the WorldChairman: Welcome to this special birthday edition of One World. Yes, folks, we've been on the air for exactly one year now, and we thought it would be a nice idea to have a special program dedicated to birthday celebrations around the world. With us in the studio tonight we have Shaheen Hag and Pat Cane, who have a weekly column on birthdays in the Toronto Daily Star. Shaheen: Good evening.Pat: Good evening.Chairman: Shaheen, perhaps we could begin with you. How are birthdays celebrated in India? Shaheen: Well, perhaps we're all assuming that everyone in the world celebrates their birthday. This just isn't the case. Low-income families in India, for instance, simply can't afford any festivities. And most Muslims don't celebrate their birthdays.Pat: I think Shaheen has raised an interesting point here. The Christian church, too, was actively against celebrating birthdays, and in any case most people, until a couple of hundred years ago, couldn't even read and wouldn't have even been able to spot their birthday on a calendar anyway. Shaheen: Of course some Muslims do celebrate their birthdays. In Egypt, Turkey and Indonesia, for example, the rich people invite friends and families around. But not in small villages. Chairman: Here in England your twenty-first used to be the big one. But now it seems to have moved to eighteen. Is that true?Pat: Yes, in most parts of the West eighteen is now the most important birthday. In Finland, for example, eighteen is the age when you can vote, you know, or buy wines, drive a car and so on. But in Japan I think you have to wait till you're twenty before you can smoke or drink. Shaheen: I know in Senegal, which is another Muslim country, girls get to vote at sixteen and boys at eighteen. And in Bangladesh, girls at eighteen and boys at twenty-one.Chairman: That's interesting. I mean is it typical that around the world girls are considered to bemore mature than boys?Shaheen: Yes, I think so, and there are some countries, particularly in South America, which have a big party only for girls. In Mexico and Argentina, for example, they have enormous parties for 15-year-old girls.Pat: You know in Norway they have a great party for anyone who's not married by the time they're thirty. It's kind of embarrassing. I mean you get pepper thrown at you.Chairman: Pepper? Why pepper?Pat: I'm not really sure.Shaheen: So does that mean that on your 29th birthday you can start thinking 'God I better get married'?Pat: Well, I'm not sure how seriously they take it.Chairman: In England we have quite big parties for your fortieth, fiftieth, sixtieth and so on. Pat: Well, in Japan your eighty-eighth is considered ...Chairman: Eighty-eighth?Pat: ... to be the luckiest birthday. Eight is a very lucky number in Japan.Questions:1. What is One World?2. What is the topic of the program?3. What do Shaheen Hag and Pat Cane do?4. Why don't some people in India celebrate their birthdays?5. According to Pat, when did people around the world begin to celebrate their birthdays?6. Why is the eighteenth birthday so important in Finland?7. Why can girls in some countries get to vote at an earlier age than boys?8. Which of the countries mentioned in the text are Muslim countries?Part CAdditional ListeningsOne World One MinuteOne World One Minute is a unique film project that invites participants in every country around the globe to record, simultaneously, one minute of their lives, one minute of our world. Sponsors of this project have chosen 12:48 GMT, September 11th 2002 as the one minute to record. At that moment exactly a year earlier began the terrorist attacks that led to the deaths of more than 2,000 people from over 60 countries. For many this will be a time of remembrance and reflection. And for others this will be an appropriate time for international communication, cooperation and sharing. It will offer them an opportunity to share a moment of their world and their life with others, an opportunity to both talk to and listen to the world, to join with others around the globe and create a truly unique record and experience. This is the idea behind the project One World One Minute.Participants are free to choose what and how to record their One Minute. Some may want to take photographs, some paint or draw pictures, while others may want to write something and record their readings. The material can be submitted to the project organizers in Scotland via e-mail or post within 6 weeks of September 11th. All the material will then be made into a feature-length film, which will capture that One Minute of our existence.The film will explore the rich diversity that is both humanity and our world. It will allow a voice to all people regardless of nationality, religion, race, political viewpoint, gender or age. Therich diversity that is Humanity shall be there for all to see.Participants will not only be kept informed of the progress of the film and the release process but will be invited to actively participate through newsletters and discussion forums.When the film is finished, it will be shown in every country of the world, both in cinemas and on TV. Contributors will be invited to attend the premiere of the film in their respective countries and will receive a full screen credit on the finished production.Statements:1. One World One Minute is a project sponsored by some filmmakers in Hollywood.2. The purpose of the project is to record how people of the world mourn the death of those who lost their lives in New York's World Trade Center.3. Participants may come from different races or nations, have different religious beliefs, and maintain opposite political viewpoints.4. Participants are invited to record one minute of their lives on any given day.5. Participants are encouraged to make short video films to record an important event in their lives.6. The project will offer people from various parts of the world an opportunity to share a moment of their life with others.7. The organizers believe that humanity is represented by the colorful variety of people's life all over the world.8. Participants are required to submit what they have recorded to organizers by e-mail not later than September 11, 2002.9. All the material submitted by the participants will be made into a feature-length film and shown on TV and in cinemas throughout the world.10. The film will become a powerful means to unite people all over the world in the war against terrorism.Part DOne World, Many UniversesOurs is, in many ways, a world without boundaries. Being a citizen of a particular nation is almost as much as being a resident of a particular town or province. Boundaries of class and caste that once shaped societies continue to fade. The freedom of people to move increases gradually with the relaxation of immigration laws in the last century. Many countries have fairly simple requirements for obtaining citizenship and voting rights.In Europe, for example, the European Union's membership has grown to 15 countries and may increase to 21 or more by 2010. It has developed a common body of laws, common policies and practices, and a great deal of cooperation among its members. The adoption of the single currency, the euro, by 12 of its member countries and the circulation of euro cash in January 2002 have enabled citizens in these countries to move about even more freely.In addition, all of the major organized religions, including Christianity, Judaism, Buddhism, Hinduism, and Islam, are alive and well, but less clearly and exclusively identified with specific cultures and geographic regions. People everywhere feel free to convert to other religions, and many people identify themselves with more than one religion.Since 1995, which is called the Year of the Internet, cyberspace has become a rich and realistic realm of experience. Its activities include the No-Self Network, which is concerned with liberation from the self. The network's members regard this liberation as an ordinary humanachievement-roughly comparable to learning to play the piano -- and not as a superhuman or divine feat. One World, Many Universes is, for me, the most persuasive mix of idealism and realism. This particular future is likely to be the most fast-changing one, rapidly evolving beyond what I have described.Questions:1. What is the passage mainly about?2. Which of the following is not mentioned in the passage as a reason that makes national boundaries less prominent?3. Which of the following is not one of the major religions mentioned in the passage?4. What enabled citizens in many EU countries to move about more freely?Unit4PartBHow to Use an OHPM: I want to use the overhead projector for my presentation. Could you show me how to use it? W: OK, let me show you. Just watch what I do. I... I'll talk you through the procedure.M: Thanks.W: Right, well. First of all, you put the OHP on the table here, about 2 meters from the wall or the screen. Er...do you have a screen?M: Er...no. I thought I'd just use the wall.W: Oh, er...well, a screen's better, but I suppose this wall will be all right. It is sort of white. Anyway, let's try it. So, the next thing you have to do is press these buttons in and lift this part up until it snaps into place.M: I see.W: And then turn it round so the head is facing towards the screen, I mean the wall, and now we can plug it in.M: Right, and you switch it on?W: Yeah. Then I press the switch here on the front...M: Right.W: There! And the light should come on.M: Right, OK.W: Yeah, there we are. So, you just place your transparency here on the glass.M: OK, there, oh!W: Oh, no! No, the other way up.M: Oh yes, of course.W: That's right, yeah. And to raise or lower the image you move this flap up or down... There, that's better.M: Right, OK.W: And finally, to focus the image you turn this wheel to make it sharp. There we are, that's not too bad.M: Oh, that's great, yeah. OK, thanks.W: Oh, one more thing: whatever you do, don't keep switching it on and off. I'm going to switch it off now. Now, when you use it in your presentation, you should leave it switched on, with a piece of paper over the glass.M: Right, I...er... I don't understand why you have to leave it on.W: Well, the reason why you have to do that is that you don't want the bulb to fail. The bulb fails easily if the machine is on and off frequently. If it does, you'll have to replace the bulb, which will be very hot and you may not have a spare anyway. So that's about it. Any questions?M: Erm...no, that seems all very clear. Thank you very much.W: You're welcome. Oh, and I really do think you need to get a screen, by the way. The picture would be much brighter than on that wall, you know.M: Oh, OK. Well, I'll ask Jim if he's got one.W: Oh, good idea! And make sure he shows you how to put it up!M: I will. Thanks again.PartCAdditional ListeningsHow to Send an E-mailM: I would like to send an e-mail to a friend of mine. Could you tell me how to do it?W: Certainly. First, you choose the e-mail program on your computer and click New Message. M: All right.W: OK? Well, then you start typing the name of the recipient. The program remembers the name and completes the e-mail address. Well, if not, you look up the name in the address book or contact list. OK? Well, if you want other people to get copies of the same message, you send them 'CCs', which are copies of the message. OK? Then you press Return on the keyboard and then you type the subject of the message. Now, there's no need to put the date because that goes in automatically when you send the message, together with the time. OK?M: Oh, yeah.W: Well, then you press Return again and start writing the message. Now, if you make a mistake, you just press Backspace to delete the previous letter or word and then type it again correctly. M: I see.W: Now, when you've finished, you read the whole message through to make sure it looks right and contains the right information. Now, if you decide you want to change sentences around, you can copy sentences and paste them in other places.M: And...er...er...how about spelling and punctuation, er...that can be corrected automatically, can't it?W: Well, yes and no. You can run your spell checker and that may bring up some mis-typings and things like that. But it definitely won't catch them all, so you must read it through to check your spelling, too. And check your punctuation at the same time. Now if you notice a misspelt word, or if you want to change a word or something like that, double-click on the word and type the new word over it.M: Fine. That's easy.W: Hmm. And then it's ready to send. You just click on Send and it'll go off immediately. And the other person will find your message in their Inbox when they next go online to get their messages. M: Right. Well, that sounds much easier than handwriting a message and faxing it.W: Sure it does.Questions:1. Where does the computer store the e-mail addresses of your friends?2. What does "CCs" stand for? When do you use "CCs"?3. What can you do if you want to change sentences around?4. What can you do if you want the computer to check mis-typings?5. What do you do if you want to change a word?PartDLayout of a LetterAs we go through, I'm going to tell you the layout of a formal letter in English -- you might want to note this information down on a separate piece of paper. OK, the first thing is to write the sender's address in the top right-hand corner. OK. This has a set order with the number of the house or flat followed by the name of the street; and then underneath that, perhaps the district if it's a big town, then under that the name of the town or city, with the postcode. And it's now common, quite acceptable, to write all this without any punctuation at all. And the address -- please write it now in the top right-hand corner -- is 12 Greenwood Avenue.And the next line is West Ealing (that's E-A-L-I-N-G). Next line: London W5-then a small gap -- 6RJ. London W5 6RJ.Now leave a line, and then write the date directly underneath the address. Now you can do this in several different ways. You can put 10 September, or September 10, or just 10 dot 9 dot 2003. So use one of these methods and put today's date in the correct place.And now, if you want, you could write the address of the person you are writing to. If you do that, you put it on the left-hand side of the paper, and you would usually start the address at roughly the same level as the date which is on the right-hand side.The next thing we write is the salutation. Our letter is to Sean White, and we begin Dear Mr. White -- please note exactly where it goes.Now, if you don't know the person's name you just put Dear Sir, or Dear Madam, or Dear Sir or Madam. In an informal letter you still use "Dear", but you start with the person's first name -- for example, Dear Maria or Dear Stephen or whatever.And at the end of the letter you sign off "Yours sincerely" -- capital "Y", but small "s". So could you write that now at the end of the letter, leaving a line first?Now, we put "sincerely" if we know the name of the person that we are writing to. But if you don't know the name, the traditional ending is "Yours faithfully". Now, this is the custom in Britain, although it is true to say that not everyone keeps to it, and I think in America they use different endings -- for example, they may finish a letter with "Truly yours".OK, if you are writing to a friend, then it's usually something like "best wishes", or often "love" if it's a member of your family or a very close friend, but not so common between two friends who are men. After the ending, in this case "Yours sincerely", leave a line, and then put your signature directly underneath. If your name is Maria Lee, write M. Lee underneath "Yours sincerely" Then type your full name below your signature. So do that now -- write your signature at the end of the letter. And that's it.Questions:1. According to the speaker, what should be included in the sender's address in a formal letter in English?2. Which of the following is not an acceptable way to date an English letter?3. What does the speaker say about addressing the receiver in a formal letter if we don't know the person's name?4. What does the speaker say about the ways to end a letter?5. When is it not advisable to end a letter with the word "love"?。
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一种新型4-DOF串并联机器人的运动控制研究1郑建勇1，李为民2，史金飞11.东南大学机械工程学院，南京 (211189)2.河北工业大学机械学院，天津 (300130）E-mail：zjy_207@摘要：文中针对4-DOF串并联机器人试验样机的研制，基于运动副分析,介绍了其主体结构3-7R并联解耦机构的构型特点，推导了机构的运动学逆解；选用了CUSNUC2100数控系统作为机器人控制系统的硬件平台, 建立了系统的控制结构；针对机器人非线性输入/输出的具体要求，建立了机器人控制轨迹模式图，设定了数控主程序。
这对开放式商用数控系统在串/并机器人控制方面的应用具有一定的理论意义。
关键词：串并联机器人；解耦；运动学；CUSNUC2100中图分类号：TP224.2 文献标识码：A1 引言目前，随着制造业和数控技术的不断发展，传统机床数控系统的研究已经比较全面了，并且已形成了一系列的标准和协议[1]。
如何利用现有商用数控系统的广泛资源，结合不同种并联机构本身的构型特点，研究和开发有针对性的并联机器人的控制系统是研究并联机器人控制问题的一种有效的方法。
构造并联机器人控制系统的思路主要有两种[2]，一种是在传统机床商用数控系统的基础上，添加并联机器人控制轨迹计算、控制指令生成与转化的模块等；另一种是开发新的专用并联机器人控制系统（如采用IPC工控机+PMAC控制卡等）。
具有解耦特性的并联机器人具有易于控制与轨迹规划的特点[3]，对解耦并联机构的研究也是并联机器人研究领域内的一个重要分支；但目前多是针对某一特定解耦并联机构进行的研究，如Clavel发现的4自由度Delta机器人机构，Lallemand，Gaudali 和Zeghloul[4]发现的2-Delta并联机器人机构，赵新华[5]提出的三自由度平移并联机器人机构，金琼和杨廷力等[6-7]分析了一类新型三平移解耦并联机构等。
解耦并联机构的各支链之间运动相互独立，克服了一般并联机构的运动耦合缺陷，研究一般机构的解耦运动对机构设计、构型优选、轨迹规划和提高加工质量都有重大的意义[8]。
文中提到的这种4-DOF串并联机器人的主体结构，是一种运动解耦的3-7R并联机构，机器人的运动控制也主要是针对3-7R并联解耦机构的控制研究。
目前的商用数控系统具备了多轴运动控制的功能，并且相对于单片机/板卡+工控机等具有较高的稳定性和可靠性。
结合4-DOF串并联机器人的控制要求，试验样机采用了CUSNUC 2100数控系统作为机器人末端执行器（吸盘）4自由度实现的控制系统。
2 4-DOF串并联机器人文中提到的4-DOF串并联机器人的主体结构如图1所示。
该机器人主要由机架、并联机构和吸盘组成，其中并联机构采用3-7R构型（R代表转动副），主要有由固定平台（机架）、动平台和三个7R支链组成。
为了使动平台仅能沿笛卡儿坐标系三个方向平动，设定各支链中的两等长杆件在结构上保持平行，从而构成平行四边形结构，限制动平台绕坐标轴的转动，构成了三自由度三平动并联结构。
选用各支链平行四边形机构底部的一个转动副与伺服电机相连，固定在机架上，作为机器人的驱动控制单元，实现机器人动平台的X向、Y向和Z1本课题得到国家自然科学基金项目（50475055）的资助。
向的运动。
各支链的平行四边形机构可在坐标轴方向上进行较大范围的摆动，使得机器人动平台具有较大范围的连续的工作空间。
选择合适的传动比，驱动伺服电机即可实现3-7R并联机构动平台在X、Y、Z坐标轴方向的快速平动和准确定位。
机器人的末端执行器是一个串接在3-7R并联机构动平台上的吸盘（用以吸放工作台上的工件），在3-7R并联机构的动平台上串接的空心伺服电机用以控制吸盘的旋转，也即增加了一个绕竖直方向旋转的自由度；空心伺服电机的作用，一方面用以控制吸盘的旋转，另一方面也用以真空吸附控制回路的通行，吸盘的吸附控制由真空吸附控制回路实现。
由于空心伺服电机固定在3-7R并联机构的动平台上，其下端通过一个法兰盘与吸盘相连，故称之为4-DOF串并联机器人。
图1 4-DOF串并联机器人Fig.1 4-DOF Series-parallel Robot3 3-7R并联解耦机构平动并联机构解耦构型研究的基本思想是：一个直线运动输入与垂直于该输入平面上的运动无关。
其物理意义如图2（a）所示。
图中，移动副P作为输入确定平面副在z坐标轴方向的位置，而平面副F沿x、y方向的运动与移动副P的输入无关。
因此，用图2（a）所示运动简图作为支链（PF），可以组成输入/输出一一对应运动解耦平动并联机构。
对支链（PF）进一步的演化，可设计如图2（b）所示的7R支链形式，其中，平行四边形机构代表移动副P，二连杆机构代表平面副F。
(a) P和F的运动简图(b)7R支链图2并联解耦机构的构型分析Fig.1 Configuration Analysis of Parallel Decoupling Mechanism由图2（b ）所示的支链进行组合即可得到图3所示的3-7R 并联解耦机构[9-10]，该机构具有以下的特点：⑴ 与定平台相连的运动副不在同一平面内，空间正交分布；三个分支的运动分别控制一个方向的移动；⑵ 每个分支所有运动副均为转动副，结构简单，成本低，制造容易；⑶ 可选用伺服电机驱动，驱动方式简单，便于控制；⑷ 与动平台相连接的三个转动副的轴线正交分布，各个分支的运动相互独立，克服了一般并联机构的运动耦合缺陷。
⑸ 该机构具有运动解耦、工作空间连续、结构和加工装配工艺简单等特点。
图3 3-7R 并联机构简图Fig.3 Three degree of freedom parallel mechanism ：（a ）structure and （b ）geometry4. 3-7R 并联机构的运动学逆解4.1坐标系的建立如图3所示，将固定坐标系o-x A y A z A 设定在机架的左上方，动坐标系P-x B y B z B 设置在动平台的几何中心上。
其中，)3,2,1(0=i m i 代表)3,2,1('11=i M M i i 的杆长，其余各参数的设定参见图3所示。
3-7R 并联机构动平台上的三个转动副的坐标如下： B 1： ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡−=⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡+++++++P P P Z r Y X l l l l l m l a )sin(cos cos )cos(sin 1'1131121111'113112011101βββθβββ （1） B 2： ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡−=⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡+++++++P P P Z Y r X l l l m l a l l )sin(cos cos sin )cos(sin '22232222210222102'2223222βββθθβββ （2） B 3： ⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡+=⎥⎥⎥⎦⎤⎢⎢⎢⎣⎡++−+++++−P P P Z Y r X m l a l l l l l a 0333103'3333332331'333333204sin )sin(cos cos )]cos(sin [θβββθβββ （3）4.2 3-7R 并联机构的运动学逆解运动学逆解即运动学的逆问题，是当并联机器人的结构参数和动平台参考点P 的位置（X P 、Y P 、Z P ）已知时，求各个分支输入运动副摆角)3,2,1(=i i θ的大小。
1. 求解输入变量)3,2,1(=i i θ)/)arcsin(()/)arcsin(()/)arcsin((310303321020221101011l a m Z l a m Y l a m X P P P +−=−−=−−=θθθ （4）2. 求解中间变量'33'22'11ββββββ、、、、、 ）（)/(]))(([arctan 222222221D U D U D V V U UV −−−−±−=β （5） 1112112111'1))sin /()cos cos arctan((βββθβ−−−−−=l r Y l l Z P P （6） ）（)/(]))(([arctan 2'2'2'2'2'2'2'2'''2D U D U D V V U V U −−−−±−=β （7） 2222222221'2))sin /()cos cos arctan((βββθβ−−−−−=l r X l l Z P P （8） ）（)/(]))(([arctan 2''2''2''2''2''2''2''2''''''3D U D U D V V U V U −−−−±−=β （9） 333204332331'3))sin /()cos cos arctan((βββθβ−−−−−−=l r X a l l Y P P （10）其中：D=12213212211122/])cos ()[(l l l l Z r Y P P −+−+−θ，r Y U P −=，2222322222212'2/))cos ()((l l l l Z r X D P P −+−+−=θ，r X U P −='，322332322331204''2/))cos ()((l l l l Y r X a D P P −+−+−−=θ，r X a U P −−=04''， 111cos θl Z V P −=，221'cos θl Z V P −=,，331''cos θl Y V P −=； 综上分析，当动平台参考点P 的位置（P X 、P Y 、P Z ）已知，321 θθθ、、均有唯一解，即运动学的逆解唯一。
而中间变量321βββ、、均有2个解，321βββ′′′、、的解分别与321βββ、、有关，而321βββ、、也只与相应支链参数有关，故中间变量的变化不影响参考点P 的位置坐标（平动解耦）。
5. 机器人的控制系统从机器人运动学的角度来看，并联机器人与串联机器人的区别在于动平台在笛卡尔坐标系中的运动是关节空间伺服运动的非线性映射（又称虚实映射）。
在串联机器人的空间坐标系中，每一套伺服驱动系统实现一个自由度，每个自由度之间的运动是独立的。
而一般并联机器人的六个自由度之间关系是耦合的，当并联机器人的动平台（末端执行器）沿空间坐标系运动时，需要各伺服驱动杆间的协调运动。