SDcamps•演辩营全国英语演讲与辩论赛
Population Growth The growth of population during the past few centuries is no proof that population will continue to grow straight upward toward infinity and doom. On the contrary, demographic history offers evidence that population growth has not been at all constant. According to paleoecologist Edward Deevey, the past million years show three momentous changes. The first,...
中文翻译: 罕见的化石记录 胚胎与幼体被保存下来在化石记录中是少见的事情。微小纤细的骨骼 通常在石化前就被食腐肉的动物拆散了，或者被风化作用破坏掉了。 鱼龙比起陆地的动物 有更大的几率被保存下来，因为它们作为海洋动物常生活在腐蚀性较小的环境中。 但是它们的石化需要一系列因素：软组织的腐烂速度缓慢，很少被其他动物残食，缺少混杂、冲走小骨头的快速水流和波浪，以及相当快地被掩埋。 当这些...
新东方优美背诵短文50篇 Unit44:Obtaining Fresh water from icebergs 44.Obtaining Fresh water from icebergs The concept of obtaining fresh water from icebergs that are towed to populated areas and arid regions of the world was once treated as a joke more appropriate to cartoons than real life. But now it is being considered quite seriously by many nations, especially since scie...
In all societies, male and female roles are regarded differently. The mother role is universally carried out by women, which is biologically based. Roles defined by sex also characterize the economic sphere so that the tasks men perform are different from those women perform. This difference is not any outgrowth of the biological differences between men and women. A specific...
Types of Speech Standard usage includes those words and expressions understood,used,and accepted by a majority of the speakers of a language in any situation regardless of the level of formality. As such, these words and expressions are well defined and listed in standard dictionaries. Colloquialisms, on the other hand, are familiar words and idioms that are understood by al...
The Goodness of Life Though there is much to be concerned about, there is far, far more for which to be thankful. Though life’s goodness can at times be overshadowed, it is never outweighed. For every single act that is senselessly destructive, there are thousands more small, quiet acts of love, kindness and compassion. For every person who seeks to hurt, there are many, man...
The Love of Beauty The love of beauty is an essential part of all healthy human nature. It is a moral quality. The absence of it is not an assured ground of condemnation, but the presence of it is an invariable sign of goodness of heart. In proportion to the degree in which it is felt will probably be the degree in which nobleness and beauty of character will be attained. Na...
新东方优美背诵短文50篇 Unit46:Vision 46.Vision Human vision like that of other primates has evolved in an arboreal environment. In the dense complex world of a tropical forest, it is more important to see well that to develop an acute sense of smell. In the course of evolution members of the primate line have acquired large eyes while the snout has shrunk to give the eye an ...
Cohesion-tension Theory Atmospheric pressure can support a column of water up to 10 meters high. But plants can move water much higher; the sequoia tree can pump water to its very top more than 100 meters above the ground. Until the end of the nineteenth century, the movement of water in trees and other tall plants was a mystery. Some botanists hypothesized that the living c...
Once upon a time there was a child ready to be born. So one day he asked God, “They tell me you are sending me to earth tomorrow, but how am I going to live there being so small and helpless?”从前，有个孩子马上就要诞生了。于是有一天他问上帝：“听说明天您就送我去人间了，但是，我这么弱小和无助，我在那儿怎么生活呢？”God replied, “Among the many angels, I chose ...
The Microscopic Technique Each advance in microscopic technique has provided scientists with new perspectives on the function of living organisms and the nature of matter itself. The invention of the visible light microscope late in the sixteenth century introduced a previously unknown realm of single celled plants and animals.In the twentieth century, electron microscopes h...
新东方优美背诵短文50篇 Unit49:Sleep 49 Sleep Sleet is part of a person’s daily activity cycle. There are several different stages of sleep, and they too occur in cycles. If you are an average sleeper, your sleep cycle is as follows. When you fist drift off into slumber, your eyes will roll about a bit, you temperature will drop slightly, your muscles will relax, and your bre...
Telecommuting Telecommuting — substituting the computer for the trip to the job–has been hailed as a solution to all kinds of problems related to office work. For workers it promises freedom from the office, less time wasted in traffic, and help with child-care conflicts. For management, telecommuting helps keep high performers on board, minimizes tardiness and a...
Muscles and Human Body It is in the joints of the human body that movements of the bones take place.The movement itself is caused by the pull of sheets and cords of very tough tissue called muscle. Muscle tissue has the special ability to shorten itself so that the bone on which it pulls has to move. When muscle tissue shortens, it also bunches up. Muscle tissue covers the b...
屋内蟋蟀 蟋蟀喜欢厨房和面包房的烘箱间，因为那些地方暖和。生活于野外的脆弱的昆虫，或者仅能愉快地度过一个短暂的夏季， 或者在沉睡中度过寒冷难受的那几个月，然而这些生活在可以说是”热带”地方的虫儿，却始终是活跃而欢快的。对于它们，熊熊的圣诞节炉火好比是三伏天的暑热。虽然在白天可以经常听到它们的唧唧鸣声，但只有夜晚才是它们天然活动的时间。一到黄昏，不仅那鸣声更为嘹亮，而...
新东方优美背诵短文50篇 Unit41:American Black Bears 41.American black bears American black bears appear in a variety of colors despite their name. In the eastern part of their range, most of these brown, red, or even yellow coats. To the north, the black bear is actually gray or white in color. Even in the same litter, both brown and black furred bears may be born. Black bear...
Pottery Ancient people made clay pottery because they needed it for their survival. They used the pots they made for cooking, storing food, and carrying things from place to place. Pottery was so important to early cultures that scientists now study it to learn more about ancient civilizations. The more advanced the pottery in terms of decoration, materials, glazes and manuf...
新东方优美背诵短文50篇 Unit42:Coal-fired power plants 42.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 ninet...
Jane Brown has been married for 12 years. She has three children, and lives in a suburb outside Columbias Higher. When her youngest child reached school age, Jane decided to go back to work. She thought that she could contribute to household finance, her salary could make a difference between a finance struggle and a secure finance situation for her family. Jane also felt bo...
The Definition of “Price” Prices determine how resources are to be used. They are also the means by which products and services that are in limited supply are rationed among buyers. The price system of the United States is a complex network composed of the prices of all the products bought and sold in the economy as well as those of a myriad of services, includin...