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The Development of WritingFew people would disagree with the belief that primitive man learned to speak long before he developed a system of writing. But while his early spoken language may have been nothing more than a few sounds, early man could transmit messages across distances by means of signals from drums, smoke and fire. It was probably a desire to record messages that led to the development of alphabets. For early man, who could speak and who could send messages, could not put those messages into permanent form. The desire to have permanent records may not be easily understood in todays world where electronic science has made disk and tape recordings commonplace. If early man wanted to leave records of past events to remind him of good times and bad, he had to depend on his memory, and on primitive markings such as piles of stones, cuttings on sticks, etc. The limitations of this system led early man to turn to rock drawings for the expression of sophisticated ideas. This form of writing depended on pictures to convey ideas, and although more advanced than previous developments, it was still too limited for man to be entirely satisfied. Man finally was able to develop a system of picture writing that associated symbols and sound. This system, which was originated by the early Sumerians and the Egyptians more than 3,000 B.C., is based on the same principle that we sue today in most world alphabets. It was about 1,000 B.C. that the Phoenicians took the complicated picture alphabets of the Egyptians and simplified then into about 30 symbols, each one standing for a consonant sound. Finally, the ancient Greeks, about 800 B.C., refined this Phoenician alphabet and added signs for vowel sounds. The alphabet used in English, an din many other world languages, is called the Roman alphabet because it was developed by the Romans who had taken most of it from another Italic people, the Etruscan, who, in their turn, had learned it from the ancient Greeks. Letters on ancient monuments in Rome prove that the Roman alphabet, the same alphabet used today, had been perfected by A.D. 114. Secret to Longevity Lies in Genes, Study FindsTue Jun 11, 5:16 PM ETby Maggie Fox, Health and Sciences CorrespondentWASHINGTON (Reuters) Want to live to be 100? Pick old grandparents. Its an old irony, but researchers said on Tuesday they had shown this is remarkably true when it comes to surviving into old age, and they believe a cluster of just a few genes may be responsible. They have set up a company that studies centenarians to see if the generic secret to living a long and healthy life may result in drugs that can prevent the diseases of aging, such as Alzheimers and heart disease. It isnt really that obvious, Dr. Thomas Perls, who led the study, said in a telephone interview. It isnt old age that runs in families. Its exceptional old age that runs in families. We think this may be a handful of genes that could be playing really substantial roles in the ability to get to very old age, much of it in good health. Perls team at Harvard University and Beth Israel Deaconess Medical School studied 444 families, including more than 2,000 relatives of people who live to 100. Demographer John Wilmoth of the University of California Berkeley compared this data to the 1900 census and the Social Security Administration database. Female siblings had death rates at all ages at about one-half the national level, they wrote in their report, published in this week issue of the Proceedings of the National Academy of Sciences. Male siblings of centenarians were at least 17 times as likely to attain age 100 themselves, while female siblings were at least eight times as likely. Perls is not interested in extending life at any cost. WHO WANTS TO GET THAT OLD, ANYWAY? People might think, who wants to live to 100 anyway? because people get the idea that the older you get, the sicker you get. But his study found just the opposite. You can get Alzheimer, stroke, cancer in your 60s and 70s and expect to live another 30,40 years. Earlier work has shown many of these people share similarities in their DNA, especially on chromosome 4. Perls hopes his company, Centagenetix () can home in on the important genes and perhaps make discoveries that will lead to drugs that can stave off disease. Discovering these genes will lead to understanding the biochemical pathways that those genes affect, he said. My hope is that that would help a lot of other people age more slowly and delay and, my goodness even escape, something like Alzheimer. Which genes you do not have may be as important as those you do, Perls said. For instance, he found the 100-year-olds were very unlikely to have a version of a gene called APOE-4, which is associated with high cholesterol and Alzheimer. Environment did not seem to be too important to those who lived to be 100. Census Bureau data showed they were more likely to be poor and poorly educated ?something not usually associated with old age. But for most of us, environment and behavior is key. I think the average set of genes gets us to our mid- to late-80s, said Perls, a geriatrician who now works at Boston Medical Center. I base this on twin studies and on Seventh Day Adventists, who have a life expectancy of 87 years, who do everything right。 They smoke, they are lean, they are vegetarian, they exercise and as a result they live 10 years longer than the rest of us. That basically tells us what our genes are capable of. But to live the extra 15, 20 years beyond that, I suspect genes are playing a greater role. So That Nobody Has To Go To School If They Dont Want by Toby Roger Sipher A decline in standardized test scores is but the most recent indicator that American education is in trouble. One reason for the crisis is that present mandatory-attendance laws force many to attend school who have no wish to be there. Such children have little desire to learn and are so antagonistic to school that neither they nor more highly motivated students receive the quality education that is the birthright of every American. The solution to this problem is simple: Abolish compulsory-attendance laws and allow only those who are committed to getting an education to attend. This will not end public education. Contrary to conventional belief, legislators enacted compulsory-attendance laws to legalize what already existed. William Landes and Lewis Solomon, economists, found little evidence that mandatory-attendance laws increased the number of children in school. They found, too, that school systems have never effectively enforced such laws, usually because of the expense involved. There is no contradiction between the assertion that compulsory attendance has had little effect on the number of children attending school and the argument that repeal would be a positive step toward improving education. Most parents want a high school education for their children. Unfortunately, compulsory attendance hampers the ability of public school officials to enforce legitimate educational and disciplinary policies and thereby make the education a good one. Private schools have no such problem. They can fail or dismiss students, knowing such students can attend public school. Without compulsory attendance, public schools would be freer to oust students whose academic or personal behavior undermines the educational mission of the institution. Has not the noble experiment of a formal education for everyone failed? While we pay homage to the homily, You can lead a horse to water but you cant make him drink, we have pretended it is not true in education. Ask high school teachers if recalcitrant students learn anything of value. Ask teachers if these students do any homework. Quite the contrary, these students know they will be passed from grade to grade until they are old enough to quit or until, as is more likely, they receive a high school diploma. At the point when students could legally quit, most choose to remain since they know they are likely to be allowed to graduate whether they do acceptable work or not. Abolition of archaic attendance laws would produce enormous dividends. First, it would alert everyone that school is a serious place where one goes to learn. Schools are neither day-care centers nor indoor street corners. Young people who resist learning should stay away; indeed, an end to compulsory schooling would require them to stay away. Second, students opposed to learning would not be able to pollute the educational atmosphere for those who want to learn. Teachers could stop policing recalcitrant students and start educating. Third, grades would show what they are supposed to: how well a student is learning. Parents could again read report cards and know if their children were making progress. Fourth, public esteem for schools would increase. People would stop regarding them as way stations for adolescents and start thinking of them as institutions for educating Americas youth. Fifth, elementary schools would change because students would find out early they had better learn something or risk flunking out later. Elementary teachers would no longer have to pass their failures on to junior high and high school. Sixth, the cost of enforcing compulsory education would be eliminated. Despite enforcement efforts, nearly 15 percent of the school-age children in our largest cities are almost permanently absent from school. Communities could use these savings to support institutions to deal with young people not in school. If, in the long run, these institutions prove more costly, at least we would not confuse their mission with that of schools. Schools should be for education. At present, they are only tangentially so. They have attempted to serve an all-encompassing social function, trying to be all things to all people. In the process they have failed miserably at what they were originally formed to accomplish.Write a summary of the following passage in less than 100 words.A great part of Arabia is desert. Here there is nothing but sand and rock. The sand is so hot that you cannot walk over it with your bare feet in the daytime. Here and there in the desert are springs of water that come from deep down under the ground- so deep that the sun cannot dry them up. There springs are few and far apart, but wherever there is one, green grass very soon covers the ground all around it. Soon fig trees and palm trees grow tall and graceful, making a cool, green, shady place around the spring. Such a place is called an oasis. The Arabs who are not in the cities live in the desert all the year round. They live in tents that can be put up and taken down very easily and quickly so that they can move from one oasis to another, seeking grass and water for their sheep, goats, camels and horses. These desert Arabs eat ripe, sweet figs, and also the dates that grow upon the palm trees; they dry them , too, and use them as food all the year round.These Arabs have the finest horses in the world. An Arab is very proud of his riding horse, and loves him almost as much as he loves his wife and children. He never puts heavy loads upon his horse, and often lets him stay in the tent with his family.The camel is much more useful to the Arab than his beautiful horse, however, for he is much larger and stronger. One camel can carry as much as or more than tow horses. The Arab loads the camel with goods, and rides him, too, for miles and miles across the desert-just as if he were really the “Ship of the Desert”, which he is often called. Summary 2Dr. Thomas Perls and resea