【正文】 ing anything else. Early bed tonight!Tuesday 13th, June Teamed up with a couple from my hotel (Peter and Terri) and hired a car. Spent all day driving around the city. There39。s a 79km roundtrip that takes in all the famous tourist spots. Stopped many times to admire the view of the city from different angles and take photographs. Now have a really good idea of what the city39。 some did not even have light but the immigrants had nowhere else to go. Their miserable stay seemed to be punishment rather than justice and freedom to them. They wrote poems on the walls about their loneliness and mourned their former life in China. In 1940 the civil authorities reformed the system so that many more Chinese people were able to grasp the opportunity of settling in the USA. Made me very thoughtful and thankful for my life today.喬治的日記（6月12日14日）6月12日 星期一清晨乘公共汽車抵達(dá)，直赴飯店，放下行李，洗澡、刮臉，即去觀光。纜車系統(tǒng)建立于1873年，是由安德魯他曾經(jīng)看到過一次可怕的交通事故：一輛馬車剎車失靈，駕車失控，車子和馬一起從山上滑了下去，很明顯這讓他受到了極大的震驚。意大利漁民在19世紀(jì)末首先來到這個地區(qū)，并且在這兒開始捕魚業(yè)。這兒也是乘渡船去天使島和海灣其他地方的渡口。今晚要早點(diǎn)睡覺!6月13日 星期二 同酒店里的一對夫妻(彼得和泰莉)作伴，一起租了一輛小汽車。有一種專門為旅游者選定的駕車游活動。這是一次79公里的旅行，它涵蓋了所有著名的旅游景點(diǎn)?，F(xiàn)在有對城市的面貌有了一個很好的了解。中國移民于19世紀(jì)50年代定居在這個地區(qū)。這兒看到了一些有趣的寺廟，不少的集貿(mào)市場和大量的餐館，還有美術(shù)館和一個博物館。打算白天再來。6月14日 星期三 早晨，從舊金山灣的港口乘渡輪去天使島，路上觀賞了金門大橋。移民站的房間又冷又潮濕，一些房間甚至沒有光，但是移民們沒有其他去處。他們在墻上寫詩，抒發(fā)孤獨(dú)的情感，痛惜以前在中國的生活。這引起我的感慨，使我對今天的生活感到欣慰。2s illnesses were more appropriate to a much older animal. Altogether Dolly lived six and a half years, half the length of the life of the original sheep. Sadly the same arbitrary fate affected other species, such as cloned mice. The questions that concerned all scientists were: Would this be a major difficulty for all cloned animals? Would it happen forever? Could it be solved if corrections were made in their research procedure? On the other hand, Dolly39。s eyes to the possibility of using cloning to cure serious illnesses and even to produce human beings. Although at present human egg cells and embryos needed for cloning research are difficult to obtain, newspapers wrote of evil leaders hoping to clone themselves to attain their ambitions. Religious leaders also raised moral questions. Governments became nervous and more conservative. Some began to reform their legal systems and forbade research into human cloning, but other countries like China and the UK, continued to accumulate evidence of the abundant medical aid that cloning could provide. However, scientists still wonder whether cloning will help or harm us and where it is leading us.克?。核鼘盐覀円蚝畏剑? 克隆一直與我們同在，而如今它還要持續(xù)下去。當(dāng)園藝師從生長著的植物上剪下枝條來培植新植物時，就會產(chǎn)生這種現(xiàn)象。實(shí)際上，這些都是自然克隆現(xiàn)象。第一，園藝師一直用它生產(chǎn)大量的供商用的植物；第二，它在對新植物物種的研究以及對動物的醫(yī)學(xué)研究方面都是很有價值的?？寺〔溉閯游锏亩啻螄L試都失敗了。它的程序如下圖所示：1．母羊(A)提供一個卵細(xì)胞。3．卵細(xì)胞準(zhǔn)備接受新的細(xì)胞核。該細(xì)胞核應(yīng)包含生產(chǎn)一頭新羊所需要的全部基因。6．用電把母羊(B)的軀干細(xì)胞核和母羊(A)的卵細(xì)胞結(jié)合起來。8．把胚胎植入另外一頭母羊(C)體內(nèi)，母羊(C)就是克隆羊的代孕者。 一方面，整個科學(xué)界都在關(guān)注著首例成功的克隆動物多莉羊的成長168。接著傳來了多莉病重的壞消息。多莉總共只存活了六年半，這是它的原型羊壽命的一半?？茖W(xué)家的腦海里產(chǎn)生的問題是：“這是不是所有克隆動物的一個主要困難呢？這種現(xiàn)象會不會永遠(yuǎn)發(fā)生？如果改進(jìn)程序，問題會不會解決？ 另一方面，多莉的出生引起了一陣強(qiáng)烈的反對，對，對媒體和公眾的想象力也產(chǎn)生了巨大的影響。 盡管目前供克隆研究的人體卵細(xì)胞和胚胎還很難得到，但報(bào)紙報(bào)道說，有些邪惡頭目希望把自己克隆出來以實(shí)現(xiàn)他的野心。各國政府惶恐不安而且更加謹(jǐn)慎，有些政府開始改革司法制度，明令禁止進(jìn)行克隆人類的研究。然而，科學(xué)察們?nèi)詫寺〖夹g(shù)有助于人類還是有害于人類，以及克隆技術(shù)將把我們引向何處困惑。s hearts. But in fact we are a long way from being able to clone extinct animals. Scientists are still experimenting with cloning mammals. This is because the cloning of mammals is still a new science and its story only began seriously in the 1950s as this list shows:1950s cloning of frogs 1996 first clone of a mammal: Dolly the sheep1970s research using the embryos of mice 2000 cow gave birth to a bison1979 work on embryos of sheep and mice 2001 China39。然而他們并不是唯一對此感到興奮的人。類似這樣的電影很受歡迎，證明了這一想法使人們感到既興奮又恐懼?？茖W(xué)家們現(xiàn)在還在進(jìn)行克隆哺乳動物實(shí)驗(yàn)，這是因?yàn)榭寺〔溉閯游锶匀贿€是一門新的科學(xué)，它是從20世紀(jì)50年代才開始進(jìn)行認(rèn)真研究的，如下表所示：20世紀(jì)50年代:克隆青蛙 1996年:首次克隆哺乳動物（多利羊）20世紀(jì)70年代:用老鼠胚胎進(jìn)行研究 2000年:母牛生野牛1979年:對羊和老鼠的胚胎進(jìn)行研究 2001年:中國首次克隆出雙胞胎小牛1981年:首次對老鼠進(jìn)行試驗(yàn)性研究 2002年:首次克隆貓1983年:首次對母牛進(jìn)行試驗(yàn)性研究 2005年:首次克隆狗 不時地會有人提議，克隆技術(shù)將有可能使地球上已經(jīng)消失的動物（如恐龍）復(fù)活。其原因有很多： ◎ 首先要求你有完好的，以提供有關(guān)細(xì)胞將如何生長的信息。群體的多樣性是指這群動物的基因要以不同的方式排列。經(jīng)過克隆的動物群體的最大缺點(diǎn)是：它們的基因排列有可能完全相同，因而它們有可能會死于同一種疾病，這樣它們也可能一個也留不下來傳種接代了。它們需要適當(dāng)?shù)臈⒌剡^正常的野生生活。事實(shí)上恐龍?jiān)?，500萬年以前就已經(jīng)消失了，所以說恐龍回歸地球的可能性僅僅是個夢想罷了！Unit Inventorsinventions 第三單元 發(fā)明家及其發(fā)明ReadingTHE PROBLEM OF THE SHRIKES When I called up my mother in the countryside on the telephone she was very upset. There are some snakes in our courtyard, she told me. Snakes e near the house now and then, and they seem to have made their home here, not far from the walnut tree. Can you get rid of them please? I felt very proud. Here was a chance for .me to distinguish myself by inventing something merciful that would catch snakes but not harm them. I knew my parents would not like me to hurt these living creatures! The first thing I did was to see if there were any products that might help me, but there only seemed to be powders designed to kill snakes. A new approach was clearly needed. I set about researching the habits of snakes to find the easiest way to trap them. Luckily these reptiles are small and that made the solution easier. Prepared with some research findings, I decided on three possible approaches: firstly, removing their habitat。 and thirdly cooling them so that they would bee sleepy and could be easily caught. I decided to use the last one. I bought an icecream maker which was made of stainless steel. Between the outside and the inside walls of the bowl there is some jelly, which freezes when cooled. I put the bowl into the fridge and waited for 24 hours. At the same time I prepared some icecubes. The next morning I got up early before the sun was hot. I placed the frozen bowl over the snakes39。 habitat in the evening, as the temperature was starting to cool. Then as before, I covered the bowl with the bucket and left everything overnight. Early the next morning I returned to see the result. This time with great caution I bent down to examine the snakes and I found them very sleepy. But once picked up, they tried to bite me. As they were poiso