新概念系列课文是永不磨灭的经典,对于学习雅思或者PTE的同学,新概念的课文可以为你提供雅思写作口语素材,PTE口语read aloud和repeat sentence进行跟读练习。更能夯实大家的语法基础。为了方便大家学习,墨尔本文波雅思将新概念三中英文对照文本和听力录音汇集在此,希望大家能好好利用,在这里学习提高。
Lesson47 Through the earth’s crust
Satellites orbiting round the earth have provided scientists with a vast amount of information about conditions in outer space. By comparison, relatively little is known about the internal structure of the earth. It has proved easier to go up than to go down. The deepest hole ever to be
bored on land went down 25,340 feet– considerably less than the height of Mount Everest. Drilling a hole under the sea has proved to be even more difficult. The deepest hole bored under sea has been about 20,000 feet. Until recently, scientists have been unable to devise a drill which would be capable of cutting through hard rock at great depths. This problem has now been solved. Scientists have developed a method which sounds surprisingly simple. A new drill which is being tested at Leona Valley Ranch in Texas is driven by a turbine engine which is propelled by liquid mud pumped into it from the surface. As the diamond tip of the drill revolves, it is lubricated by mud. Scientists have been amazed to find that it can cut through the hardest rock with great ease. The drill has been designed to bore through the earth to a depth of 35,000 feet. It will enable scientists to obtain samples of the mysterious layer which lies immediately below the earth’s crust. This layer is known as the Mohorovicic Discontinuity, but is commonly referred to as ‘the Moho’.
Before it is possible to drill this deep hole, scientists will have to overcome a number of problems. Geological tests will be carried out to find the point at which the earth’s crust is thinnest. The three possible sites which are being considered are all at sea: two in the Atlantic Ocean and one in the Pacific. Once they have determinded on a site, they will have to erect a drilling vessel which will
not be swept away by ocean currents. The vessel will consist of an immense platform which will rise to 70 feet above the water. It will be supported by six hollow columns which will descend to a depth of 60 feet below the ocean surface where they will be fixed to a huge float. A tall steel tower rising to a height of nearly 200 feet will rest on the platform. The drill will be stored in the tower
and will have to be lowered through about 15,000 feet of water before operations can begin. Within the tower, there will be a laboratory, living accommodation and a helicopter landing station. Keeping the platform in position at sea will give rise to further problems. To do this, scientists will have to devise methods using radar and underwater television. If, during the operations the drill has to be withdrawn, it must be possible to re-insert it. Great care will therefore have to be taken to keep the platform steady and make it strong enough to withstand hurricanes. If the project is successful, scientists will not only learn a great deal about the earth, but possibly about the nature of the universe itself.
污染就是我们为这个人口过密,过度工业化的星球所付出的代价。当我们开始考虑垃圾问题时,我们只有4种对付垃圾的方法:倾倒、焚烧、把垃圾变成再生材料或试图少产生一些垃圾。我们一直在试这4种方式,但是,我们在世界范围内仅产生的垃圾的量就有把我们覆盖的危险。
然而,垃圾只是我们这个星球的污染问题的一个方面。日益增长的对廉价食物的需求导致了另一种形式的污染。工业化的农作方式生产出廉价的肉类制品——牛肉、猪肉和鸡肉。使用杀虫剂和化肥生产出廉价的谷物和蔬菜。为了廉价食物我们付出代价已经太高了:牛肉中的疯牛病,鸡肉和鸡蛋中的沙门氏菌,奶制品中的利斯特杆菌。如果你想放弃肉类而变成一位素食者,那么你可以两者择一:或是选用价格昂贵、有机培植的蔬菜,或是当你认为在享用新鲜色拉和新鲜蔬菜或饮用一杯无害的水的时候,实际上每次都不断吃进杀虫剂。
但是,还有一种更加隐蔽有害的污染,它专门影响城镇地区,侵袭我们的日常生活,那就是噪音。防盗警报器在白天和黑夜的任何时候都会响起来,它的作用只是骚扰过路行人,而实际上却帮助窃贼入室行窃。在街上,汽车的防盗警报不断对我们吼叫,这是人们极度烦燥的一个原因,最近一个有关噪音的作用的调查(令人吃惊地)指出,夜间连续不断的狗叫声,在一个从1级至7级刻度表上应列为最严重的噪间污染。这个调查揭示了我们所不喜欢的大量的噪间的来源:夏天呜呜作响的割草机,公寓楼里深夜聚会的喧哗声,大声吵闹的邻居,各式各样的车辆,特别是穿越寂静的村庄的集装箱卡车,从头顶飞过的飞机和直升机,被带到公共场所、音量开到最大的大功率收音机。新技术也为噪音作了它的贡献。许多人都反对移动式电话,特别是在如饭店,公共交通车等公共场所使用移动电话。用移动电话大声交谈干扰我们的思路,破坏我们和朋友在一起轻声聊天所得到的乐趣。这个有关噪音的污染调查还揭示了一种出人意外而同时可能会引人意外而同时可能会引人发笑的老式噪音源。它竟然是鼾声。人类是这方面的罪魁祸首。调查指出,20%的35岁左右的男人打鼾;而到60岁这个年龄段,这个数字上升到令人惊愕的60%。与这些数字相比,只有5% 的女性经常打鼾;而其余则经常被与她们同睡、像吹号似地打着呼噜的男人吵醒或弄得睡不着。不管噪声来自何方,有一点是肯定的:看来寂静已变成一种珍贵的回忆。