1 . The history of microbiology begins with Dutch cloth maker named Antoni van Leeuwenhoek, a man of no formal scientific education. In the late 1600s. Leeuwenhoek, inspired by the magnifying lenses（放大镜）he used to examine cloth, built some of the first-microscopes. He developed technique to improve the quality of tiny, rounded lenses, some of which could magnify an object up to 270 times. After removing some plaque from between his teeth and examining it under a lens, Leeuwenhoek found tiny twisting creatures, which he called “animalcules”.
His observations, which he reported to the Royal Society of London, are among the first descriptions of microbes（微生物）. Leeuwenhoek discovered an entire universe invisible to the human eye. He found different microbes in samples of pond water, rain water, and human blood. He gave the first description of red blood cells, observed plant tissue, examined muscle, and investigated the life cycle of insects.
Nearly two hundred years later, Leeuwenhock’s discovery of microbes helped French chemist and biologist Louis Pasteur to develop his “theory of disease”. This concept suggested that disease originates from tiny organisms attacking and weakening the body. Pasteur’s theory later helped doctors to fight infectious diseases including anthrax, diphtheria, polio, smallpox, tetanus, and typhoid. All these breakthroughs were the result of Leeuwenhoek’s original work. Leeuwenhoek did not foresee this legacy.
In a 1716 letter, he described his contribution to science this way: “My work, which I’ve done for a long time, was not pursued in order to gain the praise I now enjoy, but chiefly from a strong desire for knowledge, which I notice resides in me more than in most other men. And therefore; whenever I found out anything remarkable, I have thought it my duty to put down my discovery on paper, so that the scientific community might be informed thereof.”
1. Which of the following best describes Leeuwenhoek?| A．trained researcher with an interest in microbiology |
| B．A curious amateur who made pioneer studies of microbes |
| C．A talented scientist interested in finding a cure for disease |
| D．A bored cloth maker who accidentally made a major discovery |
| A．the discovery of microbes |
| B．Pasteur’s theory of disease |
| C．Leeuwenhoek’s contribution |
| D．the origin of the tiny organism |
| A．He admitted that many of his discoveries happened by chance. |
| B．He considered his work to be central to later medical breakthroughs. |
| C．He was greatly concerned with improving people’s living conditions. |
| D．He believed the sharing of knowledge was a key to scientific progress |
a. Magnifying lenses were built.
b. The “theory of disease” was put forward
c. Microbes were discovered in samples of waters.
d. Leeuwenhoek’s first microscopes were successfully developed.
e. Leeuwenhoek explained his thoughts upon his own contribution.
| A．a-d-c-e-b | B．d-a-c-e-b | C．a-c-d-b-e | D．d-a-e-b-c |
2 . Babies are surrounded by human language, always listening and processing. Eventually, they put sounds together to produce a “Daddy” or a “Mama”. But what still confuses neuroscientists is exactly how the brain works to put it all together.
To figure it out, a team of researchers turned to a frequent stand-in (代替) for babies when it comes to language learning: the song-learning zebra finch. “We’ve known songbirds learn their song by first forming a memory of their father’s song or another adult’s song. Then they use that memory to guide their song learning,” said Neuroscientist Todd Roberts. “It’s been a long-term goal of the field to figure out how or where in the brain this memory is. This type of imitative learning that birds do is very similar to the type of learning that we engage in regularly—particularly when we’re young, we use it to guide our speech learning.”
Roberts and his team had a feeling that the interface (交叉区域) between sensory areas and motor areas in the brain was critical for this process, and they focused on a group of brain cells called the NIf.
“In order to prove that we could identify these circuits, we thought if we could implant a false memory.” First, they used a virus to cause the neurons (神经元) in the birds’ NIf to become sensitive to light. Then, using a tiny electrode as a flashlight, they activated (激活) the neurons. The length of each pulse of light corresponded with the amount of time the neurons would fire. And the birds’ brains interpreted that time period as the length of each note.
Soon enough, the birds began to practice the notes they had learned, even though they never really heard the sounds. Amazingly, the birds produced them in the correct social situations. The researchers say this is the first time anybody has found exactly a part of the brain necessary for generating the sorts of memories needed to copy sounds.
“This line of research is going to help us identify where in the brain we encode memories of relevant social experiences that we use to guide learning. We know that there are several neurodevelopmental disorders in people that have really far-reaching effects on this type of learning.”
1. The zebra finch is researched because its song-learning mode ________.| A．decides whether it will sing songs |
| B．helps it to say “Daddy” or “Mama” |
| C．is like the way babies learn speech |
| D．reflects its talent for imitating its father’s song |
| A．The interface in the brain. |
| B．Guidance from adults. |
| C．Imitative learning type like birds’. |
| D．The way of regular learning. |
| A．Scientists activated some neurons by using an electrode. |
| B．A bird only sings what it heard before. |
| C．The brain produces tiny electrodes. |
| D．Birds are sensitive to light. |
| A．A change in our way of listening and processing. |
| B．A chance to have relevant social experiences. |
| C．A better knowledge of the secrets of learning. |
| D．Identification of neurodevelopmental disorders. |
3 . The vaccine (疫苗) news continues to seem very encouraging. Britain started its mass vaccination effort and the U.S. isn’t far behind.
But there is still one dark cloud hanging over the vaccines that many people don’t yet understand.
The vaccines will be much less effective at preventing death and illness in 2021 if they are introduced into a population where the coronavirus is still severe—as is now the case in the U.S.
A vaccine is like a fire hose (消防龙头). A vaccine that’s 95 percent effective, as Moderna’s and Pfizer’s versions appear to be, is a powerful fire hose. But the size of a fire is still a bigger determinant of how much destruction occurs.
At the current level of infection in the U.S. (about 200,000 confirmed new infections per day), a vaccine that is 95 percent effective—distributed at the expected pace—would still leave a terrible toll (伤亡人数) in the six months after it was introduced. Almost 10 million or so Americans would catch the virus, and more than 160,000 would die.
This is far worse than the toll in a different situation where the vaccine was only 50 percent effective but the U.S. had reduced the infection rate to its level in early September (about 35,000 new daily cases). In that case, the death toll in the next six months would be kept to about 60,000.
It’s worth pausing for a moment on this comparison. If the U.S. had maintained its infection rate from September and Moderna and Pfizer had announced this fall that their vaccines were only 50 percent effective, a lot of people would have panicked.
But the reality we have is actually worse.
How could this be? No vaccine can get rid of a pandemic immediately, just as .no fire hose can put out a forest fire. While the vaccine is being distributed, the virus continues to do damage.
There is one positive way to look at this: Measures that reduce the virus’s spread—like mask-wearing, social distancing and rapid-result testing—can still have great consequences. They can save more than 100,000 lives in coming months.
1. How does the author mainly present his argument?| A．By giving definitions. | B．By categorizing facts. |
| C．By drawing comparisons. | D．By appealing to emotions. |
| A．Improving the effectiveness of the vaccines. |
| B．Producing a greater variety of vaccines. |
| C．Looking at the situation in a positive way. |
| D．Wearing masks and practicing social distancing. |
| A．The vaccines are less effective than expected. |
| B．The US have controlled the spread of the coronavirus. |
| C．The death toll in the next six months will be about 60,000. |
| D．Fewer people will die if the infection rate is lower. |
| A．The vaccine is the hope of wiping out the pandemic. |
| B．The public are optimistic about the effects of the vaccine. |
| C．The public are concerned about the high infection rate. |
| D．The distribution of vaccine will end the pandemic quickly. |
4 . Oxygen, I'm sure you'd agree, is pretty important for life on Earth. We breathe it in, our cells survive on it and without it, we hardly live. Basically all multicellular life on Earth evolved over millions of years to make use of oxygen.
But take a deep breath, because we need to talk about Henneguya salminicola, a tiny parasite(寄生虫) containing fewer than100 cells that lives within the muscle tissue of salmon, a large fish with silver skin and pink flesh. The strange-looking parasite does not busy itself with such small matters as breathing oxygen. Nope, it seems that H. salminicola is the first multicellular animal we've found that survives without the stuff.
“Aerobic respiration(有氧呼吸) was thought to be commonly found in animals, but now we confirmed that this is not the case, "said Dorothee Huchon, a zoologist at Tel Aviv University in Israel, in a press release.
Huchon and a team of international researchers examined and sequenced(排序) all of. salminicola's' genes in their study, published in the journal Proceedings of the National Academy of Sciences. They found that the parasite, which is closely related to jellyfish, lacks the DNA machinery necessary to“breathe”---it doesn't' have mitochondria(线粒体), often called the "powerhouse" of the cell, because they use oxygen to make energy. It's like a little factory inside almost all cells, and DNA detectives can find mitochondrial genes during sequencing.
The discovery came as something of an accident for the team, who were examining the genome (the complete set of genes) of the species. When they went searching for the mitochondrial genes, they came up empty-handed. "Our discovery shows that evolution can go in strange directions, ”Huchon said. "Aerobic respiration is a major source of energy, and yet we found an animal that gave up this important pathway.”
Some single-celled life forms have evolved the ability to survive without oxygen and do not have mitochondria, either. Plenty of bacteria can exist without oxygen at all. Instead of oxygen, they get their energy from fermentation(发酵) or use other molecules like iron.
But how H. salminicola produces energy is still unclear. Huchon suggests it could draw oxygen from the cells in salmon or it could have evolved similar methods to those of single-celled organisms which scientists have documented in the past.
1. What can we learn about Henneguya salminicola?| A．It is an animal consisting of a cell. |
| B．It can still survive without oxygen. |
| C．It takes on a normal appearance. |
| D．It has a longer lifespan than salmon. |
| A．To make cells breathe fast. |
| B．To help to produce oxygen. |
| C．To provide energy for cells. |
| D．To help cells absorb oxygen. |
| A．Interested. | B．Satisfied. | C．Astonished. | D．Frightened. |
| A．The natural evolution of animal cells |
| B．Different kinds of life forms on earth |
| C．A research on single-celled organisms |
| D．A creature that doesn't breathe oxygen |
5 . Great work is work that makes a difference in people’s lives, writes David Sturt, Executive Vice President of the O.C. Tanner Institute, in his book Great Work: How to Make a Difference People Love. Sturt insists, however, that great work is not just for surgeons or special-needs educators or the founders of organizations trying to eliminate poverty in sub-Saharan Africa. The central theme of Great Work, according to Sturt, is that anyone can make a difference in any job. It’s not the nature of the job, but what you do with the job that counts. As proof, Sturt tells the story of a remarkable hospital cleaner named Moses.
In a building filled with doctors and nurses doing great life-saving work, Moses the cleaner makes a difference. Whenever he enters a room, especially a room with a sick child, he engages both patients and parents with his optimism and calm, introducing himself to the child and, Sturt writes, speaking “little comments about light and sunshine and making things clean.” He comments on any progress he sees day by day (“you’re sitting up today, that’s good.”) Moses is no doctor and doesn’t pretend to be, but he has witnessed hundreds of sick children recovering from painful surgery, and parents take comfort from his encouraging words. For Matt and Mindi, whose son McKay was born with only half of a heart, Moses became a close friend. As Sturt explains, “Moses took his innate (与生俱来的) talents (his sensitivity) and his practical wisdom (from years of hospital experience) and combined them into a powerful form of patient and family support that changed the critical-care experience for Mindi, Matt and little McKay.”
How do people like Moses do great work when so many people just work? That was the central question raised by Sturt and his team at the O.C. Tanner Institute, a consulting company specialized in employee recognition and rewards system.
O.C. Tanner launched an exhaustive Great Work study that included surveys to 200 senior executives, a further set of surveys to 1,000 managers and employees working on projects, an in-depth qualitative study of 1.7 million accounts of award-winning work (in the form of nominations (提名) for awards from corporations around the world), and one-on-one interviews with 200 difference makers. The results of the study revealed that those who do great work refuse to be defeated by the constraints of their jobs and are especially able to reframe their jobs: they don’t view their jobs as a list of tasks and responsibilities but see their jobs as opportunities to make a difference. No matter, as Moses so ably exemplifies (例证), what that job may be.
1. According to Sturt, which of the following is TRUE?| A．It’s not the nature of the job, but what you do that makes a difference. |
| B．Anyone in the world is responsible to delete poverty and change the world. |
| C．Anyone can make a difference in people’s lives no matter what kind of job he does. |
| D．Surgeons, special-needs educators and founders of organizations can succeed more easily. |
| A．By keeping optimistic and calm when facing patients and their parents at hospital. |
| B．By showing his special gift and working experience when working at hospital. |
| C．By showing his sympathy and kindness to patients when entering their rooms. |
| D．By pretending to be a doctor or nurse when entering a room with a sick child. |
| A．demands | B．advantages | C．disadvantages | D．limitations |
| A．Great work is work that makes a difference in people’s lives no matter what you do. |
| B．If a boss has trouble recognizing his employees, he can ask O. C. Tanner for advice. |
| C．Moses makes a difference through his sensitivity and his practical wisdom. |
| D．Those who do great work are never defeated by others or their jobs themselves. |
6 . Hardware in general, and smartphones in particular, have become a huge environmental and health problem in the Global South’s landfill sites(垃圾填埋场).
Electronic waste (e-waste) currently takes up 5 percent of all global waste, and it is set to increase rapidly as more of us own more than one smartphone, laptop and power bank. They end up in places like Agbogbloshie on the outskirts of Ghana’s capital, Accra. It is the biggest e-waste dump in the world, where 10,000 informal workers walk through tons of abandoned goods as part of an informal recycling process. They risk their health searching for the precious metals that are found in abandoned smartphones.
But Agbogbloshie legally should not exist. The Basel Convention, a 1989 treaty, aims to prevent developed nations from unauthorized dumping of e-waste in less developed countries. The e-waste industry, however, circumvents regulation by exporting e-waste labelled as “secondhand goods” to poor countries like Ghana, knowing full well that it is heading for a landfill site.
A recent report found Agbogbloshie contained some of the most dangerous chemicals. This is not surprising: smart phones contain chemicals like mercury(水银), lead and even arsenic(砷). Reportedly, one egg from a free-range chicken in Agbogbloshie contained a certain chemical which can cause cancer and damage the immune system at a level that’s about 220 times greater than a limit set by the European Food Safety Authority (EFSA). Most worryingly, these poisonous chemicals are free to pollute the broader soil and water system. This should concern us all, since some of Ghana’s top exports are cocoa and nuts.
Some governments have started to take responsibility for their consumers’ waste. For example, Germany has started a project that includes a sustainable recycling system at Agbogbloshie, along with a health clinic for workers. However, governments cannot solve the problem alone, as there is an almost limitless consumer demand for hardware, especially when governments’ green policies are focused on issues like climate change.
Only the manufacturers can fix this. A more economically sustainable and politically possible solution is through encouraging hardware manufacturers to make the repair, reuse and recycling of hardware profitable, or at least cost-neutral.
1. What can we infer from Paragraph 2?| A．Electronic waste requires more landfill sites. |
| B．Electronic waste is too complex to get fully recycled. |
| C．Electronic products need to be improved immediately. |
| D．Electronic pollution is a burning question in Agbogbloshie. |
| A．Relaxes. | B．Abolishes. | C．Avoids. | D．Tightens. |
| A．The violation of EFSA’s standards. | B．The threat of polluted food worldwide. |
| C．The lack of diversity in Ghana’s exports. | D．The damage to chicken’s immune system. |
| A．Letting governments take on the main responsibility. |
| B．Reducing customers’ demands for electronic products. |
| C．Governments adjusting their green policies about e-waste. |
| D．Manufacturers’ developing a sustainable hardware economy. |
7 . Types of Social Groups
Life places us in a complex web of relationships with other people. Our humanness arises out of these relationships in the course of social interaction. Moreover, our humanness must be sustained through social interaction -- and fairly constantly so. When an association continues long enough for two people to become linked together by a relatively stable set of expectations, it is called a relationship.
People are bound within relationships by two types of bonds: expressive ties and instrumental ties. Expressive ties are social links formed when we emotionally invest ourselves in and commit ourselves to other people. Through association with people who are meaningful to us, we achieve a sense of security, love, acceptance, companionship, and personal worth. Instrumental ties are social links focused when we cooperate with other people to achieve some goal.
Occasionally, this may mean working with, instead of against, competitors. More often, we simply cooperate with others to reach some end without endowing the relationship with any larger significance.
Sociologists have built on the distinction between expressive and instrumental ties to distinguish between two types of groups: primary and secondary. A primary group involves two or more people who enjoy a direct, intimate, cohesive relationship with one another. Expressive ties predominate in primary groups: we view the people as ends in themselves and valuable in their own right. A secondary group entails two or more people who are involved in an impersonal relationship and have come together for a specific, practical purpose. Instrumental ties predominate in secondary groups ; we perceive people as means to ends rather than as ends in their own right. sometimes primary group relationships evolve out of secondary group relationships. This happens in many work settings. People on the job often develop close relationships with coworkers as they come to share gripes, jokes, gossip, and satisfactions.
A number of conditions enhance the likelihood that primary groups will arise. First, group size is important. We find it difficult to get to know people personally when they are milling about and dispersed in large groups. In small groups we have a better chance to initiate contact and establish rapport with them. Second, face - to - face contact allows us to size up others. Seeing and talking with one another in close physical proximity makes possible a subtle exchange of ideas and feelings. And third, the probability that we will develop primary group bonds increases as we have frequent and continuous contact. Our ties with people often deepen as we interact with them across time and gradually evolve interlocking habits and interests.
Primary groups are fundamental to us and to society. Sociologists view primary groups as bridges between individuals and the larger society because they transmit, mediate, and interpret a society’s cultural patterns and provide the sense of oneness so critical for social solidarity. Primary groups, then serve both as carriers of social norms and as enforcers of them.
1. According to Paragraph 1, which of the following statements is true of a relationship?| A．It is a structure of associations with many people. |
| B．It should be studied in the course of social interaction. |
| C．It places great demands on people. |
| D．It develops gradually over time. |
| A．Secondary group relationships begin by being primary group relationships. |
| B．A secondary group relationship that is highly visible quickly becomes a primary group relationship. |
| C．Sociologists believe that only primary group relationships are important to society. |
| D．Even in secondary groups, frequent communication serves to bring people into close relationships. |
| A．enlarge | B．evaluate |
| C．impress | D．accept |
| A．drawing comparisons between theory and practice |
| B．presenting two opposing theories |
| C．defining important concepts |
| D．discussing causes and their effects |
8 . [1] It has been said that the English and the Americans are two great people separated by one language. Among these differences, how space is treated always goes unnoticed.
[2] The middle-class American growing up in the United States feels he has a right to have his own room, or at least part of a room. American women who want to be alone can go to the bedroom and close the door. The closed door is the sign meaning “Do not disturb” or “ I’ m angry.” An American is available if his door is open at home or at his office. He is expected not to shut himself off but to maintain himself in a state of constant readiness to answer the demands of others.
[3] …?
[4] The contrasting English and American patterns have some remarkable implications, particularly if we assume that man, like other animals, has a built-in need to shut himself off from others from time to time. An English student told me what happened when hidden patterns conflicted. He was quite obviously experiencing strain(压力) in his relationships with Americans. Nothing seemed to go right and it was quite clear from his remarks that we did not know how to behave. An analysis of his complaints showed that a major source of irritation(恼怒) was that no American seemed to be able to pick up the subtle clues that there were times when he didn’t want his thoughts interrupted. As he stated it, “I’m walking around the apartment and it seems that whenever I want to be alone my roommate starts talking to me. Pretty soon he’s asking “What’s the matter?” and wants to know if I’m angry. By then I am angry and say something.”
[5] Now the picture seems quite clear. When the American wants to be alone he goes into a room and shuts the door--- he depends on spatial features for screening. For an American to refuse to talk to someone else present in the same room, to give them the “silent treatment,” is the eventual form of rejection and a sure sign of great displeasure. The English, on the other hand, lacking rooms of their own since childhood, never developed the practice of using space as a refuge from others. They have in fact internalized(内化) a set of barriers, which they erect and which others are supposed to recognize. Therefore, the more the Englishman shuts himself off when he is with an American, the more likely the American is to break in to assure himself that all is well. Tension lasts until the two get to know each other. The important point is that the spatial and spatial needs of each are not the same at all.
1. What will the paragraph 3 (which is omitted in the paper) more probably talk about?| A．The conditions of the English with regard to their understanding of space. |
| B．The response of the Americans to some unexpected demands of others. |
| C．The reaction of working class and upper class Americans to space. |
| D．The illustration of the living environment of upper-and middle-class Englishman. |
| A．prove humans are born with the need to keep themselves to themselves sometimes |
| B．demonstrate the contrasting features of the American and British problems in conflict |
| C．analyze why the British tend to be left alone without his thoughts being interrupted |
| D．stress the importance of reading delicate clues in communication with foreigners |
| A．The Americans’ failure to recognize the English’s need for space may cause the conflict. |
| B．The English prefer to tell those around not to disturb them when they are in low spirits. |
| C．The Americans are more willing to socialize with others in the workplace than the English. |
| D．The Americans will not refuse to talk to others unless they are in intense annoyance. |
| A．The difference between the English and the Americans in space lies in their use of English. |
| B．The English and the Americans have been adapted quite differently with regard to space. |
| C．The Americans have different concepts of space because they tend to enjoy more space. |
| D．The English prefer to pour their inner thoughts to others when they are in great trouble. |
9 . Vincent Van Gogh (1853-1890) is one of the most popular of the Post-Impressionist painters. He is famed for the great vitality of his works which are characterized by expressive and emotive use of brilliant color and energetic application of impastoed (厚原料的) paint.
Below are some famous pictures painted by Vincent and the poetic lyrics(歌词) to Don McLean’s hit song Vincent (Starry, Starry Night) in the famous cartoon film 《Loving Vincent》 .
| Vincent Starry, starry night, Paint your palette(画板) blue and grey, Look out on a summer’s day, With eyes that know the darkness in my soul. Shadows on the hills, Sketch the trees and the daffodils, Catch the breeze and the winter chill, In colors on the snowy linen land. Now I understand What you tried to say to me How you suffered for your sanity(精神正常) How you tied to set them free. They would not listen They did not know how Perhaps they'll listen now. Starry, starry night. Flaming flowers that brightly blaze, Swirling clouds in violet haze(阴霾,疑惑), Reflect in Vincent’s eyes of china blue. Colors changing hue, morning. field of amber(黄色的) grain, Weathered faces lined in pain, Are soothed(抚慰) beneath the artist’s loving hand. For they could not love you, But still your love was true. And when no hope was left in sight On that starry, starry night, You took your life, as lovers often do. But I could have told you, Vincent, This world was never meant for one As beautiful as you. Now I think I know what you tried to say to me, How you suffered for your sanity, How you tried to set them free. They would not listen, They're not listening sill Perhaps they never will… |
the sunflowers |
Self Portrait with Bandaged Ear | |
the Yellow House | |
Starry Night | |
Head of a Peasant Woman | |
The Potato Eaters |
1. What attitude does the writer of the song have towards Van Gogh?
| A．Prejudiced and changeable. | B．Admiring and understanding. |
| C．Doubtful but respectful. | D．Positive but contradictory. |
| A．good at drawing on starry nights | B．murdered by one of his lovers |
| C．a person full of love and beauty | D．popular with people when be was alive |
| A．The sunflowers, the Potato Eaters |
| B．Self Portrait with Bandaged Ear, Head of a Peasant Woman |
| C．the Potato Eaters, the Yellow House |
| D．Self Portrait with Bandaged Ear, Wheat Field with Crows |
10 . Kids nowadays are growing up “connected”, learning to use technology at a surprising speed. Technology is a regular part of school now! Kids as young as Kindergarten are using smartboards, IPads, and computers to complete tasks in the classroom. Older children rely on the Internet for research, getting homework, sending work to teachers, and even accessing（ 获得） textbooks. In fact, today’s kids have been given the name “digital（数字）natives” because they are facing technology almost from birth, so new things have never been a greater challenge in the hands of our children. The Internet，Facebook, iPods, pictures and texting on cell phones and all of these are the ways kids communicate today. They have become a central part of their lives. It allows them a private life that most of us know very little about.
Kids just don’t think about the results of the new world of social networking and text messaging. They don’t think that it is dangerous to send a photo of a particular person to a foolish person, who might send it to some friends that may send it to a hundred others and the next thing you know, it’s on many Facebook sites and all over the Internet forever. They don’t think that way because they don’t have the life experience that we do. We have to help them.
The key to knowing how they manage this privacy（隐私） is our “connection” to them. How closely do we connect with our kids and pay attention to what they’re doing? And how often do we talk to our children... and really listen to them? If they believe in us and know that we will be there for them, they are more likely to follow our advice. If we talk openly about what we believe in, what we stand for, those values will become their own before long.
1. What is the author’s opinion about children?| A．They are good at accepting modern things. | B．They are well understood by their parents. |
| C．They almost like to surf on the Facebook. | D．They know the Internet dangers well. |
| A．Kids. | B．Adults. | C．Internet users. | D．Internet teachers. |
| A．They only understand their own private lives. | B．They are badly influenced by new things. |
| C．They do not have life experience. | D．They don’t depend on their parents. |
| A．When they are surfing on the Internet. | B．When they meet some dangerous situations. |
| C．When parents believe in what they are doing. | D．When parents communicate with them deeply. |
