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What we call mental decay is usually a sign of ____

Some people have it easy. When their kids ask them what they do at work, they can give a simple, direct answer: “I put out fires” or “I teach primary school”. As a theoretical physicist, I never had this luck. Society has come to expect many things from the physicists. It used to be that we only had to discover the basic laws of the world and supply the techniques that would power the next Silicon Valley. With these expectations we were fairly comfortable: they are the sorts of things we think we know how to do. What makes us uncomfortable and what makes it hard for us to tell our kids what we’re up to is that in this century we have become, though unwillingly, gurus on questions such as “What is the nature of Reality?” We now deal with a whole new dass of problems. We ask how the world began and what the nature of matter is. The answers we are coming up with are just not easy to comprehend for the average person. So, when physicists get out of their cars in the morning, have a cup of coffee and sit down in front of their computers, they leave a familiar world and enter a place where things act in strange ways that are impossible for ordinary people to understand.【缺少答案，请补充】

In 1957 a doctor in Singapore noticed that hospitals were treating an unusual number of influenza-like cases. Influenza is sometimes called "flu" or a "bad cold". He took samples from the throats of patients in his hospital and was able to find the virus of this influenza. There are three main types of the influenza virus. The most important of these are type A and B, each of them having several subgroups(亚型). With the instruments at the hospital the doctor recognized that the outbreak was due to a virus in group A, but he did not know the subgroup. Then he reported the outbreak to the World Health Organization (WHO) in Geneva. WHO published the important news alongside reports of a similar outbreak in Hong Kong, where about 15~20% of the population had become ill. As soon as the London doctors received the package of throat samples, doctors began the standard tests. They found that by reproducing itself with very high speed, the virus had grown more than a million times within two days. Continuing their careful tests, the doctors checked the effect of drugs against all the known subgroups of virus type A. None of them gave any protection. This, then, was something new, a new influenza virus, against which the people of the world had no help whatever. Having found the virus they were working with, the two doctors now dropped it into the noses of some specially selected animals, which get influenza much as human beings do. In a short time the usual signs of the disease appeared. These experiments proved that the new virus was easy to catch, but that it was not a killer. Scientists, like the general public, call it simply Asian flu. The first discovery of the virus, however, was made in China before the disease had appeared in other countries. Various reportsshowed that the influenza outbreak started in China, probably in February of 1957. By the middle of March it had spread all over China. The virus was found by Chinese doctors early in March. But China was then not a member of WHO and therefore didn’t report the disease to it. Not until two months later, when the virus spread to Singapore, did the news of the outbreak reach the rest of the world. By this time it was started on its way around the world.【缺少答案，请补充】

The Ayalas were an ordinary American family just like millions of others: mom, dad, a boy and a girl. Until, that is, daughter Anissa was found to be suffering from leukemia (白血病). Her parents soon learned the dreadful truth: their daughter was under sentence of death. Leukemia patients usually die within five years without a successful bone marrow transplantation (骨髓移植). At this point Anissa’s best bet was her brother Airon, but his bone marrow proved unfit. Next, the Ayalas searched nationwide for a donor (捐赠者). Time was running out. Anissa’s final hope was a child who did not, as yet exist. Earlier the father Abe had had an operation so there would be no more children. He had to have another operation. At the age of 43 Anissa’s mother gave birth to another baby, knowing that the chances against the bone marrow of the new arrival being fit for Anissa was three to one. They were lucky. A daughter who

阅读理解一（The Ayalas的故事） The Ayalas were an ordinary American family just like millions of others: mom, dad, a boy and a girl. Until, that is, daughter Anissa was found to be suffering from leukemia (白血病). Her parents soon learned the dreadful truth: their daughter was under sentence of death. Leukemia patients usually die within five years without a successful bone marrow transplantation (骨髓移植). At this point Anissa’s best bet was her brother Airon, but his bone marrow proved unfit. Next, the Ayalas searched nationwide for a donor (捐赠者). Time was running out. Anissa’s final hope was a child who did not, as yet exist. Earlier the father Abe had had an operation so there would be no more children. He had to have another operation. At the age of 43 Anissa’s mother gave birth to another baby, knowing that the chances against the bone marrow of the new arrival being fit for Anissa was three to one. They were lucky. A daughter who could save her sister’s life was born. After a fourteen-month wait, doctors at Los Angeles’ City of Hope Hospital took a cupful of healthy bone marrow from the new baby. It was then transplanted into the body of her elder sister. Even then, doctors were not fully sure. Anissa had a 70% chance of success. Fortunately, it succeeded and Anissa’s health improved gradually. A year later, in June 1992, she got married and looked forward to a long life together with her husband.【缺少答案，请补充】

阅读理解二（Muggs的故事） Muggs was the worst of all my dogs. He always acted as if he thought I wasn’t one of the family members. There was an advantage in being one of the family members, for he didn’t bite the family as often as he bit strangers. In his last years, Muggs used to spend almost his time outdoors. As a result the garbage man, the iceman and the laundryman wouldn’t come near the house. We had to drag the garbage down to the corner take the laundry out and bring it back, and meet the iceman away from home. After this had gone on for some time we hit on a good idea for getting the dog into the house so that we could lock him up while others needed to come inside the house. Muggs was afraid of only one thing, thunder and lightning. It frightened him out of senses. He would rush into the house and hide under a bed or in a clothes closet. So we made a thunder machine out of a long narrow piece of iron with a wooden handle on one end. Mother would shake this with all her strength when she wanted Muggs into the house. I suppose it was the most complex system for running a household that was ever devised. It took a lot out of mother.【缺少答案，请补充】

阅读理解二（工作与游戏） Have you ever considered what an important part work plays in our general lifestyle? For most of us, our jobs are the main things that motivate and direct us, and around which we organize our lives. Perhaps this stress on work began with our forebears, who believed that the best way to serve God was through honest hard work, or perhaps our fundamental belief in work stems from a time when this country was young and we needed people who believed in hard work to carry out the arduous (努力的) business of pioneering. Whatever the reason, it is undeniable that work is important to us. Think about the situation that arises when you meet someone and try to learn more about him or her. An early question is very frequently something such as, “What do you do?” or “Where do you work?” This kind of question usually follows “What’s your name?” and is now so common with us that we do not stop to wonder why we ask it. But, you know, it is very possible that in the future the question will disappear, and we might very well ask instead, “What do you play?” Computer and other technological equipment are making jobs more automated (自动化的) and less personally demanding. Scientists tell us that one day in the foreseeable future, very few people will have to work. Our society will be run by computers and we will have a great deal more free time so that our games will become more important than our jobs. At the beginning of this century, almost everybody believes in work. But by the end of this century, we might be thinking quite differently. Today, people are divided into social classes in accordance with the type of work they do; tomorrow, it is more than likely we will be divided according to the type of games we play. This change may give rise to a new race of therapists called “fun specialists,” who will fill the same functions as our current career specialists. They will show us how to get the most fun and enjoyment out of our leisure time. Someday people will no longer be known primarily by the work they do.【缺少答案，请补充】

阅读理解一（Twinsburg双胞胎小镇） If twins interest you, Twinsburg will fascinate you. Every summer since 1976, this little town outside Cleveland, Ohio, has been invaded by twins. Last summer 2,356 sets of twins showed up from around the world to watch and take part in more than 100 contests. If you had been there, you might have noticed a large group of scientists who also attend the festival. Some come seeking dues to the causes of health problems-skin diseases, cancer, and heart attack, for example. Others are interested in how it feels to be a twin. But of all the scientists, perhaps the ones doing the most important work are those who study nature and nurture, that age-old question of how we come to be the kind of people we are. Why are some of us good at math, or writing, while others excel at art or basketball? What causes the differences in our intelligence, talents, and tastes? Are they largely determined by the genes we inherit from our parents (nature)? How much do our experiences in life (nurture) — the social environment we grow up in — have to do with it? If you were a scientist interested in this question, wouldn’t you love to study identical twins? Just think of it: two people who developed from the same fertilized egg. Any differences between such identical twins would have to be the result of differences in their environment. But could you also say that any similarities were the result of having the same genes? Not really. Remember, most twins share a similar environment—same house, food, relatives, and so on. The only way you could accurately measure the effects of nature and nurture, would be to study identical twins raised apart, in different environments. The scientists bring each pair of twins to the University of Minnesota for a week of intensive testing. Doctors and dentists on the team give the twins through physical examinations. They record the twins’ height, weight, eye color, ear shape and head length. Meanwhile, psychologists give the twins IQ and personality tests.【缺少答案，请补充】

If twins interest you, Twinsburg will fascinate you. Every summer since 1976, this little town outside Cleveland, Ohio, has been invaded by twins. Last summer 2,356 sets of twins showed up from around the world to watch and take part in more than 100 contests. If you had been there, you might have noticed a large group of scientists who also attend the festival. Some come seeking dues to the causes of health problems-skin diseases, cancer, and heart attack, for example. Others are interested in how it feels to be a twin. But of all the scientists, perhaps the ones doing the most important work are those who study nature and nurture, that age-old question of how we come to be the kind of people we are. Why are some of us good at math, or writing, while others excel at art or basketball? What causes the differences in our intelligence, talents, and tastes? Are they largely determined by the genes we inherit from our parents (nature)? How much do our experiences in life (nurture) --- the social environment we grow up in --- have to do with it? If you were a scientist interested in this question, wouldn’t you love to study identical twins? Just think of it: two people who developed from the same fertilized egg. Any differences between such identical twins would have to be the result of differences in their environment. But could you also say that any similarities were the result of having the same genes? Not really. Remember, most twins share a similar environment--- same house, food, relatives, and so on. The only way you could accurately measure the effects of nature and nurture, would be to study identical twins raised apart, in different environments. The scientists bring each pair of twins to the University of Minnesota for a week of intensive testing. Doctors and dentists on the team give the twins through physical examinations. They record the twins’ height, weight, eye color, ear shape and head length. Meanwhile, psychologists give the twins IQ and personality tests.【缺少答案，请补充】

The world itself is becoming much smaller by using modern traffic and communication means. Life today is much easier than it was hundreds of years ago, but it has brought new problems. One of the biggest problems is pollution. To pollute means to make things dirty. Pollution comes in many ways. We see it, smell it, drink it and even hear it. Man has been polluting the earth. The more people, the more pollution. Many years ago, the problem was not so serious because there were not so many people. When the land was used up or the river was dirty in one place, man moved to another place. But this is no longer true. Man is now slowly polluting the whole world. Air pollution is still the most serious. It’s bad for all living things in the world, but it is not the only one kind of pollution. Water pollution kills our fish and pollutes our drinking water. Noise pollution makes us angry more easily. Many countries are making rules to fight against pollution. They stop people from burning coal in houses and factories in the city, and from putting dirty smoke into the air. Pollution by $$SO_{2}$$ is now the most dangerous kind of air pollution. It is caused by heavy traffic. We are sure that if there are fewer people driving, there will be less air pollution. The earth is our home. We must take care of it. That means keeping the land, water and air clean. And we must take care of the rise in pollution at the same time.【缺少答案，请补充】

Laura walked towards the man. “It is terribly cold,” she said. “Colder than ever,” the man said. “Now tell me what the hell you want.” He stared at Laura for a few seconds, and then grinned, “Maybe you’d like to come inside and warm up.” “No, No, I don’t want to come in.” She took a deep breath. “I just wanted to know if you’re interested in selling your dog.” “That worthless mutt?” The man pointed to a dog in the yard and laughed for a few seconds, then suddenly stopped. “I was just joking about the worthless part. He’s a pretty good dog. Yeah. I might be interested.” “Well, he’s the kind of dog I’m looking for, and it doesn’t look to me like you’re too fond of him. I mean he’s tied up outside. I don’t see any food or water.” “You just wait a minute. I take good care of that dog. The guy I got him from said he was a trained guard dog. Trouble is the stupid thing doesn’t even bark when strangers come around. But then I guess that wouldn’t matter to you. You’re probably just looking for a pet, huh?” “Yeah, well here’s your chance to get rid of him. I’ll give you twenty dollars.” He snorted(哼着鼻子说). “You expect me to sell a purebred guard dog for twenty dollars? Fifty dollars. That’s my price. You bring me fifty dollars, honey, and you got yourself a dog.” The man smiled. “Sure you don’t want to come in?” Laura shook her head. “I’ll be back with the money.” Breakfast forgotten, she searched for and found a cash machine four blocks away. I can’t afford this, she thought as she punched the numbers into the machine. The dog will need a vet(兽医) and where am I going to get the money for that? Her fears faded(消退) as she pictured the dog, curled up, not outside on the cold, hard ground, but in front of a glowing fireplace. Blue ceramic bowls filled with food and water sat in the corner of the kitchen, and she saw him, head held high, matching her stride on their daily walk. With the money in her purse she hurried back to the man’s house.【缺少答案，请补充】

When Berenice Belizaire arrived in New York from Haiti with her mother and sister in 1987, she was not very happy. She spoke no English. The family had to live in a small and crowded Brooklyn apartment, a far cry from the comfortable house they’d had in Haiti. Her mother, a nurse, worked long hours. School was torture(折磨). Berenice had always been a good student, but now she was learning a new language while enduring constant taunts(嘲笑) from the Americans. They cursed(咒骂) her in the cafeteria and threw food at her. Someone hit her sister in the head with a book. “Why can’t we go home?” Berenice asked her mother. Because home was dangerous. The schools weren’t always open anymore, and education --- her mother insisted --- was the most important thing. Her mother had always pushed her: memorize everything, she ordered. “I have a pretty good memory,” Berenice admitted last week. Indeed, the other kids at school began to notice that Berenice always, somehow, knew the answers. “They started coming to me for help,” she says. “They never called me a nerd(书呆子).” Within two years Berenice was speaking English, though not well enough to get into one of New York’s elite(精英的) public high school. She had to settle for a neighborhood school, James Madison, a school with a history of unlikely success stories. “I didn’t realize what we had in Berenice at first,” says math teacher Judith Khan. “She was good at math, but she was quiet. And the things she didn’t know! She applied for a summer program in Buffalo and asked me how to get there on the subway. But she always seemed to ask the right questions. She understood the big ideas. She could think on her feet. She could explain difficult problems so the other kids could understand them. Eventually I realized she wasn’t just pushing for grades, she was hungry for knowledge… And you know it never occurred to me that she was also doing well in English and history, all these other subjects that had to be much tougher for her than math.”【缺少答案，请补充】

When Berenice Belizaire arrived in New York from Haiti with her mother and sister in 1987, she was not very happy. She spoke no English. The family had to live in a small and crowded Brooklyn apartment, a far cry from the comfortable house they’d had in Haiti. Her mother, a nurse, worked long hours. School was torture. Berenice had always been a good student, but now she was learning a new language while enduring constant taunts from the Americans. They cursed her in the cafeteria and threw food at her. Someone hit her sister in the head with a book. “Why can’t we go home?” Berenice asked her mother. Because home was dangerous. The schools weren’t always open anymore, and education — her mother insisted — was the most important thing. Her mother had always pushed her: memorize everything, she ordered. “I have a pretty good memory,” Berenice admitted last week. Indeed, the other kids at school began to notice that Berenice always, somehow, knew the answers. “They started coming to me for help,” she says. “They never called me a nerd.” Within two years Berenice was speaking English, though not well enough to get into one of New York’s elite public high school. She had to settle for a neighborhood school, James Madison, a school with a history of unlikely success stories. “I didn’t realize what we had in Berenice at first,” says math teacher Judith Khan. “She was good at math, but she was quiet. And the things she didn’t know! She applied for a summer program in Buffalo and asked me how to get there on the subway. But she always seemed to ask the right questions. She understood the big ideas. She could think on her feet. She could explain difficult problems so the other kids could understand them. Eventually I realized she wasn’t just pushing for grades, she was hungry for knowledge… And you know it never occurred to me that she was also doing well in English and history, all these other subjects that had to be much tougher for her than math.”【缺少答案，请补充】

How do young children learn to have good values How can parents teach their children about the importance of kindness, patience, and self-discipline At a time when more and more parents worry about the negative and violent images their children see on TV, in the movies and, on the Internet, some are turning to fairy tales as a way to teach their young ones how to behave in society. Fairy tales were not always intended for children. We know this because some of these stories have existed for hundreds of years and were passed down from generation to generation through songs and drama. They were considered entertainment for everyone, not only for young people. In these ancient stories, the heroes were extremely clever, fiercely independent, and never gave up. Over the years, some of the heroes’ qualities and story lines have been changed to fit the times. Psychologists think that fairy tales have a positive influence on children because they present the two sides of good and evil very clearly. When children hear the stories, they develop sympathetic feelings for the heroic characters. In each tale, they can see that there are many different kinds of people in the world and that we all have a choice about what kind of person we want to be. We can choose to do good actions, rather than bad ones, in our lives. What kind of values can children learn from fairy tales in "The Princess and the Pea," a poorly dressed girl who insists she is a princess is given a difficult test by the Queen. When she passes the test, we learn that she is rewarded because she stayed true to herself. In "The Little Mermaid," the mermaid who lives under the sea longs to be with the humans on land. Through her experiences, we learn about the importance of living with and accepting other cultures. In "Pinocchio," a wooden puppet turns into a boy when he finally learns how to tell the truth. Teaching values is the reason most often given for teaching literature and encouraging reading. These old stories can indeed teach us lessons about human relationships that are universal enough to survive throughout the centuries. This might be the reason why they have been around for so long and are unlikely to disappear any time soon.【缺少答案，请补充】

There are two things I can count on my dad asking every time he calls me: "Is there anything I can do for you?" and "How's the car?" I guess he asks what he can do for me because his dad (an air force officer) was never really there for him, and he's determined to provide me with the support he lacked. During my youth he never missed a school play or softball game. In fact, he was so supportive that I sometimes longed for one of those dads who dressed better and cared less. But my dad would forever be the guy wearing shorts with dress shoes and black socks, cheering me on, expecting greatness. His other standard question- "How's the car?" - used to strike me as a waste of long-distance dollars from a man who once suggested making a list of what you want to talk about before calling someone out of state. What I now realize is that "How's the car?" is not about the car. It's a father's way of asking his adult daughter how she is. The advantage is that if there's something wrong with the car, he knows what to do about it and how much it will cost, whereas if you're having marital problems or doubting a career choice, he might have to put Mom on the line. At age 30 I finally took the plunge into adulthood by leasing a car without my dad's help or advice. I'm sure my dad was hurt rather than proud. Though a daughter's independence is evidence of a job well done, it still implies the job's done, and many fathers are reluctant to retire. Even when my dad was overworked, he'd happily hop on a plane if I said I needed help. His frequent question, "Is there anything I can do for you?" underlines the fact that he wishes there was still something he could provide. It's interesting: Even though we're tied by blood and I love him no matter what, he still seems to need a concrete function - suggesting stocks, finding the cheapest plane fare - to feel he has a role in my life.【缺少答案，请补充】

What is a librarian? A person who sits at a little desk, talking in a very low voice, taking books from people who bring them back, making them pay if they have them too long, and stamping the date on books that are taken out? Certainly not! That is the work of the most junior employee in the library. To become a qualified librarian, you first have to work in a library school, usually for two years. If you pass your exams successfully, you may apply for a senior post in a public library. Many librarians are university graduates, and they only have to spend one year training instead of two. Every English town (and many large villages too) has a public library. The head librarian has the important task of deciding in which way to spend the money provided by the local government. He buys the books. So he must know the community he lives in, and which books the people there want and need most. A public library in an agricultural area, for example, would not have very much demand for a book on the problem of air pollution in large cities. However, people in the area may be studying any subject under the sun, and these students quite often depend on the services of their public library. Librarians are usually asked to advise on the design of new library buildings; so modern libraries are far friendlier to readers than those built in the last century. As libraries are open such long hours, the librarian’s working timetable may be very different from that of his friends. On some evenings he has to work. But, having such an important position in the cultural life of where he lives, he can never complain that his job is boring or unimportant.

successfully, you may apply for a senior post in a public library. Many librarians are university graduates, and they only have to spend one year training instead of two. Every English town (and many large villages too) has a public library. The head librarian has the important task of deciding in which way to spend the money provided by the local government. He buys the books. So he must know the community he lives in, and which books the people there want and need most. A public library in an agricultural area, for example, would not have very much demand for a book on the problem of air pollution in large cities. However, people in the area may be studying any subject under the sun, and these students quite often depend on the services of their public library. Librarians are usually asked to advise on the design of new library buildings; so modern libraries are far friendlier to readers than those built in the last century. As libraries are open such long hours, the librarian’s working timetable may be very different from that of his friends. On some evenings he has to work. But, having such an important position in the cultural life of where he lives, he can never complain that his job is boring or unimportant.【缺少答案，请补充】

My friend Mike was shaking his head in disbelief. “That young woman who just waited on me,” he said, pointing to an employee of the fast food restaurant where we were eating, “had to call someone over to help her count change. The cash register showed her I needed 99 cents, but she couldn’t figure out how to count out the coins.” I understood Mike’s concern. What we have done in this country, although unintentionally, is to create several generations of individuals most of whom have no idea how to reason; how to do simple math; how to do research; or finally, how to be creative. The reason for this is our overuse of information technology: video games, television, digital watches, calculators, and computers. Information technology feeds us information without requiring us to think about it and let us perform operations without understanding them. It is time we took a hard look at an educational system that only teaches our children how to push buttons. Our kids can’t tell time if the clock has hands. They can use calculators, but cannot add, subtract, divide, or multiply. Video games have taken the place of active, imaginative play. Although most of them are technically literate, they choose not to read. They are so used to television and movies that they cannot use their imagination to stay interested in a book. It is not enough to recognize that a problem exists. What we need is a solution. The one I offer is simple to suggest, but may be impossible to carry out. We must unplug our children. If we don’t, they will never learn how to solve problem. They will never learn even basic reasoning skills and will certainly not develop creativity. Instead of filling classrooms with electronics, let’s concentrate on food old-fashioned literacy —reading books. Students must be taught not to perform computer operations by rote, but to figure and reason for themselves. They must see how things work and how processes lead to results, they must also stretch their imagination.【缺少答案，请补充】

Perhaps you are an average student with average intelligence. You do well enough in school, but you probably think you will never be a top student. This is not necessarily the case, however. You can receive better grades if you want to. Yes, even students of average intelligence can be top students without additional work. Here’s how: 1. Plan your time carefully. Make a list of your weekly tasks. Then make a schedule or chart of your time. Fill in committed time such as eating, sleeping, meetings, classes, etc. Then decide on good, regular times for studying. Be sure to set aside enough time to complete your normal reading and work assignments. Of course, studying shouldn’t occupy all of the free time on the schedule. It’s important to set aside time for relaxation, hobbies, and entertainment as well. This weekly schedule may not solve all of your problems, but it will make you more aware of how you spend your time. Furthermore, it will enable you to plan your activities so that you have adequate time for both work and play. 2. Find a good place to study. Choose one place for your study area. It may be a deck or a chair at home or in the school library, but it should be comfortable, and it should not have distractions. When you begin to work, you should be able to concentrate on the subject. 3. Skim before you read. This means looking over a passage quickly before you begin to read it more carefully. As you preview the material, you get some idea of the content and how it is organized. Later when you begin to read you will recognize less important material and you may skip some of these portions. Skimming helps double your reading speed and improves your comprehension as well. 4. Make good use of your time in class. Listening to what the teacher says in class means less work later. Sit where you can see and hear well. Take notes to help you remember what the teacher says. 5. Study regularly. Go over your notes as soon as you can after class. Review important points mentioned in class as well as points you remain confused about. Read about these points in your textbook. If you know what the teacher will discuss the next day, skim and read that material too. This will help you understand the next class. If you review your notes and textbook regularly, the material will become more meaningful and you will remember it longer. Regular review leads to improved performance on tests. 6. Develop a good attitude about tests. The purpose of a test is to show what you have learned about a subject. The world won’t end if you don’t pass a test, so don’t worry excessively about a sin le test. Tests provide grades, but they also let you know what you need to spend more time studying, and they help make your new knowledge permanent. There are other techniques that might help you with your studying. Only a few have been mentioned here. You will probably discover many others after you have tried these. Talk with your classmates about their study techniques. Share with them some of the techniques you have found to be helpful. Improving your study habits will improve your grades.【缺少答案，请补充】

Many of us believe that a person’s mind becomes less active as he grows older. But this is not true, according to Dr. Jarvik, professor of psychiatry at the University of California. She has studied the mental functioning of aging persons for several years. For example, one of her studies concerns 136 pairs of identical twins, who were first examined when they were already 60 years old. As Dr. Jarvik continued the study of the twins into their 70s and 80s, their minds did not generally decline as was expected. However, there was some decline in their psycho-motor speed. This means that it took them longer to accomplish mental tasks than it used to. But when speed was not a factor, they lost very little intellectual ability over the years. In general, Dr. Jarvik’s studies have shown that there is no decline in knowledge or reasoning ability. This is true not only with those in their 30s and 40s, but with those in their 60s and 70s as well. It is true that older people themselves often complain that their memory is not as good as it once was. However, much of what we call “loss of memory” is not that at all. They usually are incomplete learning in the first place. For example, the older person perhaps had trouble hearing, or poor vision, or inattention, or was trying to learn the new thing at too fast a pace. In the cases where the older person’s mind really seems to decay, it’s not necessarily a sign of decay due to old age. Often it is simply a sign of depressed emotional state.【缺少答案，请补充】