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 . 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 |
3 . It is an honor for me to deliver this speech and on behalf of the graduating students, welcome you to this special ceremony 2020.
This is a unique moment. We are stepping up to another phase of our lives at a time of great hardship and global difficulties. Hope this ceremony will help erase sad memories, refresh beautiful ones and add more splendid memories into our lives.
I was born in the middle of war, which caused my family to move to Serbia for three years. When the war ended, we returned to Bosnia. My mother, who is and will ever be my heroine, was the only figure who guided me, provided for me and kept me on the right track, in the hope for a better life. I owed her so much as she is responsible for huge part of my success. I will always remember her teachings “to complain less and always find solutions at the price of whatever it takes” ， which brought me to China, an ancient land of new hopes.
During the COVID-19 outbreak, I got the best opportunity to understand China. I saw millions of people united with one goal-to win the battle against this epidemic. I have never seen such a collective dedication from a nation, turning things for the better by sacrificing personal convenience on a grand scale. China's governance and health care system proves to be one of the most efficient in the world. With a population of 1.4 billion, China not only has successfully controlled the transmission of the corona-virus but also assisted many other countries across the globe.
Everyone has a role to play in the battle against the virus. In Tsinghua, I played a tiny but necessary role: Staying on campus, studying online, cooperating during temperature checks and respecting social distancing measures. The rules set by the university and Chinese government had everyone's health and safety as first priority. This made me feel safe and confident that China was on the right track towards victory. Throughout this time, despite the immense challenges, Tsinghua has facilitated many online conferences, which helped me nurture more skills in my field of study.
Friends, we are now graduating from one of the world’s most prestigious universities. Tsinghua has been like a mother to us over the past months and years, guiding and nurturing us along the way, providing us with great vision and placing on us high expectations. So what comes next? Actions speak louder than words. Let us accept new challenges, think beyond our limits and keep in mind the ethics of life.
Let's undertake everything we can for the sake of unity, humanity and the international community. Let's work together for a more promising future and prosperous world.
1. In the author's eyes, the special ceremony 2020 should| A．be a unique moment to mourn the sacrificed |
| B．be a time to wave a heartfelt goodbye to adversities |
| C．be a moment to open a new chapter of life |
| D．be a glorious time to embrace a beautiful past |
| A．The author came to China so as to escape from wars |
| B．The author witnessed how the original virus spread swiftly |
| C．The author was requested to supply medical aid to the fight against COVID-19 |
| D．Owing to dozens of timely measures,China had a ideal control of the virus |
| A．The strict rules of the government. |
| B．The joint commitment of the nation. |
| C．The harsh circumstance in China. |
| D．The great transformation of the school. |
4 . 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. |
5 . Modern medicine’s ability to keep us alive makes it tempting to think human evolution may have stopped. But if we look at the rate of our DNA’s evolution, we can see that human evolution hasn’t stopped – it may even be happening faster than before.
Evolution is a gradual change to the DNA of a species over many generations. It can occur by natural selection, when certain traits created by genetic changes help an organism survive or reproduce. Such genes are thus more likely to be passed on to the next generation, so they increase in frequency in a population. Gradually, these changes and their associated traits become more common among the whole group.
By looking at global studies of our DNA, we can see evidence that natural selection has recently made changes and continues to do so. Though modern healthcare disrupts a key driving force of evolution by keeping some people alive longer, in countries without access to good healthcare, populations are continuing to evolve. Survivors of infectious disease outbreaks drive natural selection by giving their genetic resistance to offspring. Our DNA shows evidence for recent selection for resistance of killer diseases like Lassa fever and malaria. Selection in response to malaria remains in regions where the disease remains common.
Humans are also adapting to their environment. Gene change allowing humans to live at high altitudes have become more common in populations in Tibet, Ethiopia, and the Andes. The spread of genetic changes in Tibet is possibly the fastest evolutionary change in humans, occurring over the past 3,000 years. This rapid increase in frequency of a mutated gene that increases blood oxygen content gives locals a survival advantage in higher altitudes, resulting in more surviving children.
Diet is another source for adaptations. Studies show that natural selection favoring a change allowing adults to produce lactase – the enzyme (酶) that breaks down milk sugars – is why some groups of people can digest milk. Over 80 per cent of northwest Europeans can, but in parts of East Asia, where milk is much less commonly drunk, an inability to digest lactose is the norm. Like high altitude adaptation, selection to digest milk has evolved more than once in humans and may be the strongest kind of recent selection.
Yet, despite these changes, natural selection only affects about 8 per cent of our genome. But scientists can’t explain why some genes are evolving much faster than others. We measure the speed of gene evolution by comparing human DNA with that of other species. One fast-evolving gene is human accelerated region 1 (HAR1), which is needed during brain development. A random section of human DNA is on average more than 98 per cent identical to the chimp comparator, but HAR1 is so fast evolving that it’s only around 85 per cent similar. Though scientists can see these changes are happening – and how quickly – we still don’t fully understand why fast evolution happens to some genes but not others.
1. Which of the following statements may the author agree with?| A．Evolution occurs among several people overnight. |
| B．Genes may change and some are beneficial to people’s lives. |
| C．Evolution is done when the whole population possesses a certain gene. |
| D．The changed genes leading to higher survival rates are chosen deliberately. |
| A．explains | B．causes | C．upsets | D．heals |
| A．some people can resist infectious diseases like malaria |
| B．children in Tibet tolerate living environments with thin air |
| C．northwestern Europeans digest lactose better than East Asians |
| D．the human gene HAR1 resembles that of a chimp to a lesser extent |
| A．What Is Natural Selection? |
| B．Are Humans Still Evolving? |
| C．Why Will Certain Genes Evolve? |
| D．How Do Mutated Genes Function? |
6 . It’s late in the evening, time to close the book and turn off the computer. You’re done for the day. What you may not realize, however, is that the learning process actually continues in your dreams.
It might sound like science fiction, but researchers are increasingly focusing on the relationship between the knowledge and skills our brains absorb during the day and the often strange imaginings they generate at night. Scientists have found that dreaming about a task we’ve learned improves performance in that activity (suggesting that there’s some truth to the popular idea that we’re “getting” a foreign language once we begin dreaming in it). What’s more, dreaming may be an essential part of understanding, organizing and retaining what we learn.
While we sleep, research indicates, the brain replays the patterns of activity it experienced during waking hours, allowing us to enter what one psychologist calls a neural (神经的) virtual reality. A vivid example of such replay can be seen in a video researchers made recently about sleep disorders. They taught a series of dance moves to patients suffering from sleepwalking and related conditions. They then videotaped the subjects as they slept. Lying in bed, eyes closed, one female patient on the tape performs the dance moves she learned earlier.
This shows that while our bodies are at rest, our brains are drawing what’s important from the information and events we’ve recently encountered, then integrating that material into the vast store of what we already know. In a 2010 study, researchers reported that college students who dreamed about a computer maze (迷宫) task they had learned showed a 10-fold improvement in their ability to find their way through the maze compared with participants who did not dream about the task.
That study’s chief researcher Herbert Smith suggested that studying right before bedtime or taking a nap following a study session in the afternoon might increase the probability of dreaming about the material. Think about that as you go to sleep tonight.
1. What happens when one enters a dream state?| A．The body continues to act as if the sleeper were awake. |
| B．The neural activity of the brain will become intensified. |
| C．The brain once again experiences the learning activities of the day. |
| D．The brain behaves as if it were playing a virtual reality video game. |
| A．It replaces old information with new material. |
| B．It processes and absorbs newly acquired information. |
| C．It regroups information and places it in different files. |
| D．It systematizes all the information collected during the day. |
| A．Staying up late before finally going to bed. |
| B．Having a period of sleep right after studying. |
| C．Having a dream about anything you are interested in. |
| D．Thinking about the chances of dreaming about the material. |
| A．How study affects people’s dreams. |
| B．Why people learn more after sleeping. |
| C．What time students should study and sleep. |
| D．How dreaming may lead to improved learning outcomes. |
7 . Art has always been a polarizing(分化的)subject.Some people like realism,others like abstract.But do you know why some people value art in the millions,while others see the same piece as little more than a child’s finger painting?
Many consider art to be quite random in terms of our likes and dislikes.But according to new research,there may actually be a scientific reason behind our fondness for certain works.The answer lies in how a person’s brain breaks down the visuals(视觉效果)of a painting combined with their judgment.
To prove their theory,neuroscientist(神经科学家)Kiyohito Iigaya and his team from the California Institute of Technology(Caltech)gathered more than 1,300 volunteers and asked them to rate 825 different paintings from four different art genres(类型).
After analyzing the data,scientists found that the same groups of people tended to prefer similar aspects of the same paintings.These characteristics were then grouped into“low-level”features like color and blending,and“high-level”features like the emotion behind the painting.
From this experiment,Caltech’s system was then able to predict an individual’s specific taste in art and organize different works into one group,according to the paintings’features and volunteers’preferences.
In a second test,researchers repeated the experiment on six volunteers,showing each 1,000 paintings while inside an MRI—a machine that scans a person’s brain activity.The test revealed(揭示)that the different features of a painting are sent to the part of the brain that deals with valuing items,allowing someone to form their overall opinion.
Finally,the team repeated the first test on new volunteers.Again,the algorithm(算法)was able to accurately predict individuals’art preferences.According to Iigaya,this shows that the factors that contribute to whether a person likes an image are universal,not random.
Lesley Fellows,a neurologist at McGill University who studies value judgments,stated,“We know a lot about‘how’the brain carries out actions,but‘why’is far less well understood.”
1. What did the Caltech team try to discover?| A．What kinds of artwork appeal to people. |
| B．Why only some people value art. |
| C．Whether an individual’s preference for art is predictable. |
| D．Whether one’s mood influences their opinion of artwork. |
| A．Some features of paintings were categorized（分类）. |
| B．It helped decide the types of paintings to be used. |
| C．Part of the brain to process paintings was identified. |
| D．Volunteers were grouped based on their response. |
| A．The brain reacted differently to different paintings. |
| B．MRIs influence people’s opinion of paintings. |
| C．Individuals have different valuing systems in their brain. |
| D．A certain part of the brain helps people judge paintings. |
| A．To question the Caltech team’s research. |
| B．To approve of the research on why we make value judgments. |
| C．To show there is still a lot left to learn about the brain. |
| D．To point out the focus of the future brain research. |
8 . 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. |
9 . Last summer, two nineteenth-century cottages were rescued from remote farm fields in Montana, to be moved to an Art Deco building in San Francisco. The houses were made of wood. These cottages once housed early settlers as they worked the dry Montana soil; now they hold Twitter engineers.
The cottages could be an example of the industry’s unusual love for “low technology”, a concept associated with the natural world, and with old-school craftsmanship（手艺）that exists long before the Internet era. Low technology is not virtual (虚拟的) —so, to take advantage of it, Internet companies have had to get creative. The rescued wood cottages, fitted by band in the late eighteen-hundreds, are an obvious example. Other companies are using a broader interpretation（阐释）of low technology that focuses on nature.
Amazon is building three glass spheres filled with trees, so that employees can “work and socialize in a more natural, park-like setting.” At Google’s office, an entire is carpeted in glass. Facebook’s second Menlo Park campus will have a rooftop park with a walking path.
Olle Lundberg, the founder of Lundberg Design, has worked with many tech companies over the years. “Our tech engineers are the ones who feel impoverished, because they’re surrounded by the digital world,” he says. “We’ve found that introducing real crafts is one way to regain their individual identity.”
This craft-based theory is rooted in history. William Morris, the English artist and writer, turned back to pre-industrial arts in the eighteen-sixties, just after Industrial Revolution. The Arts and Crafts movement defined itself against machines. “Without creative human occupation, people became disconnected from life.” Morris said.
Research has shown that natural environments can restore our mental abilities. In Japan, patients are encouraged to “forest-bathe”, taking walks through woods to lower their blood pressure.
These health benefits apply to the workplace as well. Rachel Kaplvin, a professor of environmental psychology, has spent years researching the restorative effects of natural environment. Her research found that workers with access to nature at the office - even simple views of trees and flowers - felt their jobs were less stressful and more satisfying. If low-tech offices can potentially benefit the brains and improve the mental health of employees then, fine, bring on the cottages.
1. The writer mentions the two nineteenth-century cottages to show that _________| A．Twitter is having a hard time |
| B．Old cottages are in need of protection |
| C．Early settlers once suffered from a dry climate in Montana |
| D．Internet companies have rediscovered the benefits of low technology |
| A．is related to nature | B．is out of date today |
| C．cosumes too much energy | D．exists in the virtual world |
| A．Critical | B．positive |
| C．worried | D．doubtful |
| A．Past Glories, Future Dreams |
| B．The Virtual World, the Real Challenge |
| C．High-tech Companies, Low-tech Offices |
| D．The More Craftsmanship, the Less Creativity |
10 . The way Jason Momoa describes Hawaii’s beloved inactive volcano, Mauna Kea, makes you understand why it’s considered sacred(神圣的).
"It’s kind of the umbilical cord(脐带) to earth," the actor tells CNN. "You know, if you think about the Hawaiian islands, that’s the biggest mountain in the world, right? All the way up. So Mauna Kea is the most sacred. We call it the belly button, too. That’s like our birthplace. That’s how our islands were formed. So how can that not be sacred?"
He would know. Jason, a native of Hawaii, has had a near-constant presence there when he’s not working, fighting with local protestors to stop the construction of the Thirty Meter Telescope, or TMT, which would drill directly into the mountain and invade its precious water supply. So far, protestors have successfully blocked the only road crews seeking to go up the mountain in order to build the billion-dollar observatory.
"It started in 2015. What’s happening over there was just not right," Jason says. "And I went over there to meet with everyone to bring the point to the world." Jason joins the protests when he can. He cared so deeply about the preservation of the land that when he had spare time to lend his support, he was there. "You also have to remember, that’s our water source. So having an 18-story building built on top of the tallest mountain from the sea level on our water level is terrible."
The Game of Thrones star says he feels the movement is working and describing his part in it as a calling to do what he feels right in his soul. "There’s massive progress that’s bringing our people together," he says, adding, "I think there are a lot of problems in Hawaii. There are a lot of things that have happened in our history, a lot of injustice, and so we’re shining a light on it. People like myself or Dwayne Johnson, Bruno Mars are trying to spread the concern all around the world. For my soul I need to be there."
1. Why is Mauna Kea sacred according to Jason?
| A．It’s still growing upwards. | B．It looks like the belly button. |
| C．It’s the birthplace of Humans. | D．It brings the islands into being. |
| A．The project of building TMT. | B．The event of blocking the road crews. |
| C．The shooting of Game of Thrones. | D．The movement of preserving the land. |
| A．Bringing Hawaiian people together. | B．Witnessing the history of Hawaii. |
| C．Bringing Hawaii problems into focus. | D．Making Mauna Kea better-known. |
| A．Travel. | B．Celebrity. |
| C．Culture. | D．Technology. |
