SDcamps•演辩营全国英语演讲与辩论赛
Animals’ Compasses Researchers have found that migrating animals use a variety of inner compasses to help them navigate. Some steer by the position of the Sun. Others navigate by the stars. Some use the Sun as their guide during the day and then switch to star navigation by night. One study shows that the homing pigeon uses the Earth’s magnetic fields as a guide ...
Raising Oysters In the past oysters were raised in much the same way as dirt farmers raised tomatoes – by transplanting them. First, farmers selected the oyster bed, cleared the bottom of old shells and other debris, then scattered clean shells about. Next, they “planted” fertilized oyster eggs, which within two or three weeks hatched into larvae. The larva...
树 我想我永远也不会看到 象一棵树那样优美的诗篇， 树那饥渴的嘴唇紧紧贴住 大地乳汁甘美的胸脯， 它整天仰望着上帝， 举起枝叶繁茂的手臂祈祷， 它那茂密如发的枝叶里 夏天会筑起知更鸟的安乐窝， 雪花飘落在它怀里， 它同雨水亲密无间。 诗歌出自我等愚人之手， 而树却是造化的天工。 乔埃斯·基尔默 (1) prest: pressed的变体，为了与下面一行最后一个词breast押韵而采用。 (2)flowing breast： 相当于b...
Plankton Scattered through the seas of the world are billions of tons of small plants and animals called plankton. Most of these plants and animals are too small for the human eye to see. They drift about lazily with the currents, providing a basic food for many larger animals. Plankton has been described as the equivalent of the grasses that grow on the dry land continents...
Movie Music Accustomed though we are to speaking of the films made before 1927 as “silent”, the film has never been, in the full sense of the word, silent.From the very beginning, music was regarded as an indispensable accompaniment; when the Lumiere films were shown at the first public film exhibition in the United States in February 1896, they were accompanied ...
The traditional holidays in our house when I was a child were spent timing elaborate meals around football games. My father tried to make pleasant chitchat and eat as much as he could during halftime. At Christmas he found time to have a cup or two of holiday cheer and do his holly-shaped bow tie1. But he didn’t truly shine until Valentine’s Day. I don’t kn...
A Curious Decision A poor chimney-sweeper, who had not enough money to buy a meal, stopped one hot summer day at noon before an eating-house, and remained regaling his nose with the smell of the victuals. The master of the shop told him several times to go away, but the sweep(1) could not leave the savory smell, though unable to purchase the taste of the food. At last the co...
The Early Settlers in North America The North American frontier changed some of the characteristics of the pioneers of the 1750’s and intensified others.They were, as a group, semiliterate, proud, and stubborn, as dogged in their insistence on their own way of life as pine roots cracking granite to grow.Perhaps their greatest resource was their capacity to endure. They...
Coal-fired Power Plants The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap, readily available fuel with which to generate large amounts of electric power. Coal seemed to fit the bill, and it fueled the earliest power stations (which were set up at the end of the nineteenth century by Edison himself. As more power plants were...
The Source of Energy A summary of the physical and chemical nature of life must begin, not on the Earth, but in the Sun; in fact, at the Sun’s very center. It is here that is to be found the source of the energy that the Sun constantly pours out into space as light and heat. This energy is liberated at the center of the Sun as billions upon billions of nuclei of hydrog...
Bacteria Bacteria are extremely small living things. While we measure our own sizes in inches or centimeters, bacterial size is measured in microns. One micron is a thousandth of a millimeter: a pinhead is about a millimeter across. Rod-shaped bacteria are usually from two to four microns long, while rounded ones are generally one micron in diameter. Thus if you enlarged a r...
A little Girl Sitting on a grassy grave, beneath one of the windows of the church, was a little girl.(1) With her head bent back(2) she was gazing up at the sky and singing, while one of her little hands was pointing to a tiny cloud that hovered like a golden feather above her head. The sun, which had suddenly become very bright, shining on her glossy hair, gave it a metalli...
Scientific Theories In science, a theory is a reasonable explanation of observed events that are related. A theory often involves an imaginary model that helps scientists picture the way an observed event could be produced. A good example of this is found in the kinetic molecular theory, in which gases are pictured as being made up of many small particles that are in constan...
The History of Chemistry Chemistry did not emerge as a science until after the scientific revolution in the seventeenth century and then only rather slowly and laboriously. But chemical knowdedge is as old as history, being almost entirely concerned with the practical arts of living. Cooking is essentially a chemical process; so is the melting of metals and the administratio...
The Satiric Literature Perhaps the most striking quality of satiric literature is its freshness,its originality of perspective.Satire rarely offers original ideas.Instead, it presents the familiar in a new form. Satirists do not offer the world new philosophies.What they do is to look at familiar conditions from a perspective that makes these conditions seem foolish, harmful...
Schooling and Education It is commonly believed in the United States that school is where people go to get an education.Nevertheless, it has been said that today children interrupt their education to go to school. The distinction between schooling and education implied by this remark is important. Education is much more open-ended and all-inclusive than schooling. Education ...
The Language of Music A painter hangs his or her finished pictures on a wall, and everyone can see it. A composer writes a work, but no one can hear it until it is performed. Professional singers and players have great responsibilities, for the composer is utterly dependent on them. A student of music needs as long and as arduous a training to become a performer as a medical...
Topaz Topaz is a hard, transparent mineral. It is a compound of aluminum, silica, and fluorine. Gem topaz is valuable. Jewelers call this variety of the stone “precious topaz”. The best-known precious topaz gems range in color from rich yellow to light brown or pinkish red. Topaz is one of the hardest gem minerals. In the mineral table of hardness, it has a rati...
Choosing An Occupation Hodeslea, Eastbourne, November 5, 1892 Dear Sir, I am very sorry that the pressure of other occupations has prevented me from sending an earlier reply to your letter. In my opinion a man’s first duty is to find a way(1) of supporting himself, thereby relieving other people of(2) the necessity of supporting him. Moreover, the learning to do work o...
The Rainy Day The day is cold,and dark,and dreary; It rains,and the wind is never weary; The vine still clings to the moldering wall, But at every gust the dead leaves fall, And the day is dark and dreary. My life is cold and dark and dreary; It rains and the wind is never weary; My though still cling to the moldering past, But the hopes of youth fall thick in the blast, And...