SDcamps•演辩营全国英语演讲与辩论赛
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 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...
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...
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...
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...
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...
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...
Changing Roles of Public Education One of the most important social developments that helped to make possible a shift in thinking about the role of public education was the effect of the baby boom of the 1950’s and 1960’s on the schools. In the 1920’s, but especially in the Depression conditions of the 1930’s, the United States experienced a declining...
The Beginning of Drama There are many theories about the beginning of drama in ancient Greece. The one most widely accepted today is based on the assumption that drama evolved from ritual. The argument for this view goes as follows. In the beginning, human beings viewed the natural forces of the world – even the seasonal changes – as unpredictable, and they sough...
Love your life However mean your life is,meet it and live it ;do not shun it and call it hard names.It is not so bad as you are.It looks poorest when you are richest.The fault-finder will find faults in paradise.Love your life,poor as it is.You may perhaps have some pleasant,thrilling,glorious houres,even in a poor-house.The setting sun is reflected from the windows of the a...
初雪 初雪飘临。多么美啊！它整日整夜那么静静地飘着，落在山岭上，落在草地上，落在世人的屋顶上，落在死才的坟墓上！在一片白茫茫之中，只有河流在美丽的画面上划出一道曲曲弯弯的黑线；还有那叶儿落净的树木，映衬着铅灰色的天空，此刻更显得枝丫交错，姿态万千。初雪飘落时，是何等的宁谧，何等的幽静！一切声响都趋沉寂，一切噪音都化作柔和的音乐。再也听不见马蹄得得，再也听不见车轮辚辚！唯有雪橇...
Andrew Carnegie Andrew Carnegie, known as the King of Steel, built the steel industry in the United States, and, in the process, became one of the wealthiest men in America. His success resulted in part from his ability to sell the product and in part from his policy of expanding during periods of economic decline, when most of his competitors were reducing their investments...
Friends A true friend is someone who reaches for your hand and touches your heart. There’s always going to be people that hurt you,so what you have to do is keep on trusting and just be more careful about who you trust next time around. Make youself a better person and know who you are before you try and know someone else and expect them to know you. Remember:Whatever ...
Lighthouses The first navigational lights in the New World were probably lanterns hung at harbor entrances. The first lighthouse was put up by the Massachusetts Bay Colony in 1716 on Little Brewster Island at the entrance to Boston Harbor. Paid for and maintained by “light dues” levied on ships, the original beacon was blown up in 1776. By then there were only a...
My mother is a kind and gentle woman. She is very busy from morning till night. As a teacher she works diligently and efficiently. As Mother, she takes good care of us and gives us every comfort. I have an elder brother. He and I both love her dearly, as she loves us. My mother has been teaching maths at a middle school in my home town. She goes to the school early in the mo...
Marine Mammals Since there is such an abundance of food in the sea,it is understandable that some of the efficient, highly adaptable, warm-blooded mammals that evolved on land should have returned to the sea.Those that did have flourished. Within about 50 million years — no time at all, geologically speaking — one of the four kinds of mammals that has returned to...
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 than 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 unimpeded view. Of mammals only humans an...
Plants in the Deserts Some cacti, like the saguaro, grow to tree size, but true trees need more moisture than most desert environments can supply, so they are scarce on deserts. Close to streambeds, cottonwoods can sometimes be found. Though these streams are dry most of the year, water flows there longest and is usually available fairly close to the surface. Elsewhere, tree...