1 . The scientists who re-engineered the plastic-eating enzyme(酶) PETase have now created a new enzyme called “cocktail” , which can digest plastic up to six times faster.
PETase breaks down PET back into its building blocks, creating an opportunity to recycle plastic and reduce plastic pollution. PET is the most common thermoplastic(热塑性塑料) used to make single-use drinks bottles, which takes hundreds of years to break down in the environment, but PETase can shorten this time to days. The initial discovery set up the prospect of a revolution in plastic recycling, creating a potential low-energy solution to tackle plastic waste.
Now, the same trans-Atlantic team have combined PETase and its “partner”, a second enzyme called MHETase, to generate much bigger improvements: simply mixing PETase with MHETase doubled the speed of PET breakdown, and engineering a connection between the two enzymes to create a “super-enzyme”, increased this activity by a further three times.
The team was co-led by the scientists who engineered PETase, Professor John McGeehan and Dr Gregg Beckham. Professor McGeehan said: “Gregg and I were chatting about how PETase attacks the surface of the plastics and MHETase chops things up further, so it seemed natural to see if we could use them together. Our first experiments showed that they did work better together, so we decided to physically link them. It took a great deal of work, but it was worth the effort — we were delighted to see that our new enzyme is up to three times faster than the separate enzymes.”
The original PETase enzyme discovery indicated the first hope that a solution to the global plastic pollution problem might be within grasp, though PETase alone is not yet fast enough to handle the tons of PET bottles. Combining it with a second enzyme, and finding together they work even faster, means another leap forward has been taken towards finding a solution to plastic waste. PETase and the new combined MHETase-PETase both work by digesting PET plastic. This allows for plastics to be made and reused endlessly, reducing our reliance on fossil(化石) resources.
1. What can we learn about “cocktail” from the text?| A．It doubles the breakdown of plastics. |
| B．It takes hundreds of years to break down. |
| C．It contributes to breaking down plastic quickly. |
| D．It deals with the plastic waste three times faster. |
| A．A new study of PET. | B．The breakdown of PET. |
| C．The discovery of PETase. | D．The functions of PETase. |
| A．Co-leading the trans-Atlantic team. | B．Combining PETase and MHETase. |
| C．Attacking the surface of the plastics. | D．Talking about conducting experiments. |
| A．PET pollution is no longer a difficult problem to deal with. |
| B．New enzyme is speeding up our reliance on fossil resources. |
| C．MHETase-PETase makes the world free from plastic pollution. |
| D．Plastic-eating enzyme “cocktail” promises new hope for plastic waste. |
2 . A company called Compass Pools has some good news for height and swimming enthusiasts.Recently，the company announced their novel design—a first of its kind 360degree pool which is set to be placed on a skyscraper in London.The Infinity London will be the first and only building in the world to include this cuttingedge pool design.The pool will be laid on top of a 55story skyscraper and will allow people to float over 200 meters above the London skyline with unobstructed(没有障碍的) views of the city.
The entrance to the pool is hidden.People began to raise questions about how anyone would get inside the pool.Compass Pools explains：“Swimmers will access the pool through a rotating spiral(螺旋形的) staircase based on the door of a submarine，rising from the pool floor when someone wants to get in or out.”
But that is not the only unique technology of the pool.The designers found a way to make sure the wind doesn't blow the water down to the streets.They included a builtin anemometer(风力计) to monitor the wind speed.It is linked to a computercontrolled building management system which will also take care of the temperature of the water.
Alex Kemsley promises that this unique pool will surpass everyone's expectations.“It's quite a strange feeling to swim in the SkyPool at The Shard and have helicopters flying past at your level but this pool takes it a step further，”he says.“Putting your goggles(游泳镜) on and with a 360degree view of London from 220m up，it really will be something else—but it's definitely not one for the acrophobic(恐高的)！”
While the exact date of the construction is not clear yet，if things go well，it may begin in 2022.The location has yet to be confirmed too.
1. What can we learn from the first paragraph?| A．The Infinity London is the only building to swim in. |
| B．Swimmers can enjoy the views of London in the pool. |
| C．The pool is located on the first floor of a skyscraper. |
| D．Compass Pools has built many 360degree pools in the world. |
| A．How to get a view of London. |
| B．How to monitor the wind speed. |
| C．How to get into or out of the pool. |
| D．How to keep the water in the pool. |
| A．People who enjoy flying. |
| B．People who lose weight. |
| C．People who fear heights. |
| D．People who have poor sight. |
| A．It is not certain when people can swim in it. |
| B．The exact location of the construction is clear. |
| C．Swimmers can expect its designs easily. |
| D．It's impossible to monitor the temperature of the water. |
3 . It was New Year's night. An aged man was standing at a window. He raised his sad eyes towards the deep blue sky, where the stars were floating like white lilies (百合花) on the surface of a clear calm lake. Then he cast them on the earth, where few more hopeless people than himself moved towards their certain goal—the tomb. He had already passed sixty of the stages leading to it, and he had brought from his journey nothing but errors and regrets.
The days of his youth appeared like dreams before him, and he remembered the serious moment when his father placed him at the entrance of the two roads—one leading to a peaceful, sunny place, covered with flowers, fruits and resounding with soft, sweet songs; the other leading to a deep, dark cave, which was endless, where poisonous snakes hissed and crawled.
He saw a star fall from the sky and disappear, and this was the symbol of himself. His regret, which was like a sharp arrow, struck deeply into his heart. Then he remembered his friends in his childhood, who entered on life together with him. But they had made their way to success and were honored and happy on this New Year's night. With shame and grief he dared no longer look towards that heaven where his father lived. His darkened eyes were full of tears, and with a despairing effort, he let out a cry, “Come back, my early days! Come back！”
And his youth did return, for all this was only a dream which he had on New Year's night. He was still young though his faults were real; he had not yet entered the deep, dark cave, and he was still free to walk on the road which leads to the peaceful and sunny land.
As for those who still remain at the entrance of life, hesitating to choose the bright road, remember that when years have passed and your feet fall on the dark mountains, you will cry bitterly, but in vain, “Oh youth, return! Oh give me back my early days！”
1. What does the underlined word “them” in the first paragraph refer to?| A．The lilies. | B．The stars. |
| C．The people. | D．The eyes. |
| A．They had also made many mistakes. |
| B．They kept in close touch with him. |
| C．They had made major achievements. |
| D．They looked down on him. |
| A．His father died. |
| B．His father lived far away. |
| C．His father returned home. |
| D．His father gave him two choices. |
| A．It's no use crying for help. |
| B．It's vital to value your childhood. |
| C．They should not wait to choose the right way. |
| D．They should be careful at the entrance of life. |
4 . Bird pattern carved on Yubi in Chinese, comes alive and circles around, while an audio guide introduces the cultural relic and the bird’s connotation (寓意). Such is the experience of watching a cultural relic through a pair of augmented reality (AR) glasses at the Liangzhu Museum.
The museum displays various burial objects found in the Archaeological Ruins of Liangzhu City in Hangzhou, showcasing the civilization of prehistoric rice agriculture and a state-level society between 3,300 B.C. and 2,300 B.C. The site was included on the UNESCO World Heritage List in July 2019, providing profound and compelling evidence that Chinese civilization started 5,000 years ago.
Using AR to tell Liangzhu’s ancient story and let the young people sense and feel close to cultural relics through modern technology is an important task at the museum, making it a pioneer in using modern technology and a hot place for tourists.
“I found that most students were very curious about it, and it could inspire students to have the desire to learn more,” said Chen Xi, the AR glasses provider. “I’ve never seen this before. The illustration of the ancient wild birds above is not that clear. But with the AR glasses, I know what the ancient wild bird exactly looks like and how it is different from what we see on TV,” said Rong Mei, a visitor in her twenties. “Compared with traditional ways of appreciating a cultural relic, AR glasses guide has virtual images which help people visually understand the information behind the relic, such as in which life scenarios was the relic used, its function and its cultural connotation,” said Zhou Liming, director of the Liangzhu Museum.
From digitalization to intelligentization (智能化), the Liangzhu Museum took more than five years. It started to collect the digital information of the ruins and relics since 2015. It paves the way for the museum to deliver Liangzhu’s story through multimedia approaches to attract more people, especially the youth, as modern technology bridges the gap between young people and cultural relics.
1. What is the crucial significance of Liangzhu cultural relics?| A．Unearthing various prehistoric burial objects. |
| B．Representing the world’s earliest rice culture. |
| C．Enriching the UNESCO World Heritage List. |
| D．Confirming China’s 5,000-year-old civilization. |
| A．To inspire the curiosity of students. |
| B．To show the aim and effects of using AR glasses. |
| C．To highlight hi-tech brings people close to cultural relics. |
| D．To present opinions of appreciating cultural relics vary. |
| A．The discovery of the cultural relics. |
| B．The restoration of the ruins and relics. |
| C．The process of forming intelligentization. |
| D．The reconstruction of the Liangzhu Museum. |
| A．Stories behind the AR Glasses |
| B．Adventures in Liangzhu Museum |
| C．A New Chapter for Liangzhu Museum |
| D．An Encounter with the Prehistoric China |
5 . Full stops intimidate young people when used in social media communication as they are interpreted as a sign of anger, according to linguistic experts.
Teenagers and those in their early twenties, classified as Generation Z, have grown up with smart phones which they use to send short messages without full stops. Linguistic experts are now investigating why teens interpret a correctly-punctuated(加标点)text as a signal of irritation. According to experts, youngsters used to communicating electronically break up their thoughts by sending each one as a separate message, rather than using a full stop, which they use only to signal they are annoyed or irritated.
In 2015, a study from Binghamton University in New York suggested that people who finish messages with full stops are perceived as insincere. The study involved 126 undergraduates and the researchers found that text messages ending in the most final of punctuation marks- eg, “Let's go together.”- were perceived as being less sincere. Unusually, texts ending in an exclamation (感叹) point-“I'm proud of you!”-are deemed heartfelt or more profound.
Research leader Celia Klin said at the time: “When speaking, people easily convey social and emotional information with eye gaze, facial expressions, tone of voice, pauses and so on. However, people obviously can't use these mechanisms when they are texting. Thus, it makes sense that texters rely on what they have available to them - emoticons, deliberate misspellings that mimic speech sounds and, according to our data, punctuation.”
The full stop derives from Greek punctuation introduced by Aristophanes of Byzantium(拜占庭的阿里斯多芬尼斯：古希腊早期喜剧代表作家、诗人)in the 3rd Century BC.
1. What does the underlined word “they” in paragraph 1 refer to?| A．Young people. | B．Full stops. |
| C．Social media tools. | D．Linguistic experts. |
| A．Teens never use a full stop in all short messages. |
| B．Teens used to use a full stop, but they don't now. |
| C．Teens break up thoughts by sending a separate message. |
| D．Teens consider a full stop to be insincere and formal. |
| A．Neutral. | B．Subjective. |
| C．Approving. | D．Critical. |
| A．Long history of the full stop. |
| B．New interpretation of the full stop. |
| C．Fundamental usage of the full stop. |
| D．Mysterious disappearance of the full stop. |
6 . The Pharos, the great lighthouse of Alexandria, was one of the Seven Wonders of the Ancient World. It stood on the island of Pharos, in the harbor of the city of Alexandria. In 290 B.C, Ptolemy I Soter, the ruler of Egypt, ordered the building of the lighthouse. Twenty years later, it was finished−the first lighthouse in the world and the tallest building on Earth except the Great Pyramid of Egypt.
The Pharos was designed by Sostrates, a Greek architect. Sostrates wanted to leave his name on the base of the lighthouse. But Ptolemy refused, ordering that only his own name appear on the building. But Sostrates found a way to do that. At the base of the Pharos, Sostrates left a message containing his own name. Then he covered it with plaster (建筑石膏) and left Ptolemy's name over it. After many years, the plaster disappeared and people knew the true architect of the lighthouse.
In 1302 and 1323, two strong earthquakes hit Alexandria, and the lighthouse was damaged. In 1326, it finally fell into the sea. Much of what we know about the lighthouse comes from the writings of Arabs who once visited the Pharos.
The Pharos was about 384 feet tall, the same height as a modern 40-storey building. At the top of the lighthouse stood a large statue of Poseidon, the Greek god of the sea. Under it was a beacon, the source of light for the lighthouse. The Pharos used two kinds of beacons. At night, a large fire created the light. During the day, a huge mirror made use of the sunlight to create the light.
It was said that the mirror was also used to set enemy ships on fire as they entered the harbor by directing the sun’s rays (sunlight) at them. Although it is clearly impossible, the idea is interesting.
1. Why did Sostrates use plaster at the base of the Pharos?| A．To follow Ptolemy's orders. |
| B．To hide his name left on the base. |
| C．To protect the base from damage. |
| D．To make the lighthouse more beautiful. |
| A．For about 800 years. | B．For about 1,000 years. |
| C．For about 1,600 years. | D．For about 2,000 years. |
| A．The lighthouse. | B．The statue. |
| C．A large fire. | D．A huge mirror. |
| A．Sostrates and Ptolemy. |
| B．The function of an old lighthouse. |
| C．The Pharos, a wonder of the ancient world. |
| D．The architect of an old lighthouse. |
7 . In 2015, Chennai was destroyed by one of the worst floods in over a century, leaving thousands without food, water and supplies. During the flood, many heroes arose, one of whom was Santosh, a young man who owned a take-out restaurant in Chennai.
When the first flood hit in November, he got a call from a company called Naga Rava. The company asked him to prepare 5,000 packets of food and give them to the flood victims. He, with his partners, took the order, cooked for 14 hours and delivered(递送) them. But that night, as they sat together discussing the event of the day, they actually felt ashamed(羞愧). “Here was a man not even from Chennai and he was going out of his way to help the affected people. We, while living here, had not really done anything ourselves for our own people,” said Santosh later.
He then began the groundwork for a collection to help cook more dishes. Little did he know that the November flood was just the beginning, and the real show was about to begin. The December flood affected them all. His own house got flooded and his family was trapped on the second floor. They lost phone connection and electricity. In spite of this, Santosh went back out into the flood, creating a kitchen and preparing food all by himself for the victims.
He did not sleep for four days, taking a one-hour break every day as he kept on cooking. As word got out about this man’s effort, others stepped out to join him. From children to the elderly, strangers came to help him in cooking, packing and transporting food. Up to 300 volunteers worked together to make it all happen. By the time the fourth day finally came to an end, Santosh and his team had prepared 170,000 food boxes and delivered them to people in need.
1. What inspired Santosh to help the affected people?| A．A call for help. | B．His cooking skills. |
| C．An act of kindness of a stranger. | D．The encouragement from his partners. |
| A．The help and support. | B．The severer flood. |
| C．Santosh’s family suffering. | D．Santosh’s cooking more food. |
| A．Energetic and helpful. | B．Determined and clever. |
| C．Selfless and caring. | D．Kind and wise. |
| A．Many Hands Make Light Work |
| B．Kindness Is Its Own Reward |
| C．Major Floods Brought Challenges To People |
| D．A Man Cooked 170,000 Meals For The Affected |
8 . Genealogy, or researching your family tree, is a hobby that can rapidly develop into an obsession. Before you start looking for your own ancestors, read this advice from genealogist Maria McLeod.
The first question to ask yourself is why you want to research your family tree. Genealogy is not about discovering that you are the lost prince or princess of an unknown kingdom. It’s about finding more about yourself. For most people the important question is “Why am I like I am?” You might not look like other members of your immediate family and you want to know where your green eyes or curly hair come from. You may be curious about why you have such a quick temper. You may even be suffering from a medical condition and want to know if something in your genetic makeup has caused it.
Another common motivation for researching your family tree is that you plan to visit the place that your ancestors came from and you secretly hope that you will find some long lost cousins with whom you can share your memories. There can be few more exciting things than meeting a distant cousin who is living on the other side of the globe and finding that she looks just like your younger sister. But you should also bear in mind that they may not necessarily want to have anything to do with you. Sometimes there are skeletons in the cupboard that you and your branch of the family are unaware of, but which are still fresh in the minds of your more distant relatives.
Once you are clear about your motivations, you need to take a moment to think about just how many ancestors you might have and how far back you intend to go. You have, no doubt, thought about your parents’ parents and your parents’ parents’ parents. But go back ten generations and the picture becomes much more complicated. You can work it out for yourself. You may be descended(遗传) from no fewer than 1,024 people through ten generations. This can mean that you spend hours going through official records, either in person at the records office or on the Internet. Are you prepared for such a huge task?
1. What might be Maria Mcleod’s first piece of advice be?| A．Be prepared to accept your bad temper. |
| B．Don’t expect to find lovely relatives. |
| C．Be prepared to find out your hidden health problems. |
| D．Don’t expect to find out you are a member of a royal family. |
| A．You may bring back bad memories. |
| B．They find it disturbing to entertain you. |
| C．They suspect you of having wrong motives. |
| D．You could remind them of their lost loved ones. |
| A．Who your great grandparents are. |
| B．When you can finish your huge task. |
| C．Why researching a family tree is complex. |
| D．How many people you are descended from. |
| A．Uncovering family secrets: do you dare? |
| B．The science of genealogy: new developments |
| C．Expert opinions on researching your family past |
| D．A step-by-step guide to researching your family tree |
9 . Scientists say they've developed a system using machine learning to predict when and where lighting will strike. The research was led by engineers from the Swiss Federal Institute of Technology in Lausanne, Switzerland.
European researchers have estimated that between 6,000 and 24,000 people are killed by lightning worldwide each year. The strikes can also cause power outages, destroy property, damage electrical equipment and start forest fires. For these reasons, climate scientists have long sought to develop methods to predict and control lightning. In the United States and other places, ground-based sensing devices are used to identify strikes as they happen. But, no system has been created to effectively predict lightning.
The system tested in the experiments used a combination of data from weather stations and machine learning methods. The researchers developed a prediction model that was trained to recognize weather conditions that were likely to cause lightning.
The model was created with data collected over a 12-year period from 12 Swiss weather stations in cities and mountain areas. The data related to four main surface conditions: air pressure, air temperature, relative humidity and wind speed.
The atmospheric data was placed into a machine learning algorithm（算法）, which compared it to records of lightning strikes. Researchers say the algorithm was then able to learn the conditions under which lightning happens.
Amirhossein Mostajabi is a PhD student at the institute who led the development of the method. He said, “current systems for gathering such data are slow and complex and require costly collection equipment like radar or satellites.”
“Our method uses data that can be obtained from any weather station,” Mostajabi said. “This will improve data collection in very remote areas not covered by radar and satellite or in places where communication systems have been cut,” be added.
The researchers plan to keep developing the technology in partnership with a European effort that aims to create a lightning protection system. The effort is called the European Laser Lightning Rod project.
1. Why have climate scientists tried to predict and control lighting?| A．To collect relative data. |
| B．To reduce the destruction lightning has been causing. |
| C．To create a scientific system. |
| D．To do research in relation to machine learning. |
| A．air pollution | B．wind speed |
| C．relative humidity | D．air temperature |
| A．lighting. | B．the system being tested. |
| C．the atmospheric data. | D．the machine learning algorithm. |
| A．He developed the method and the system himself. |
| B．He thinks the current systems are too slow and simple. |
| C．He is a professor at the Swiss Federal Institute of Technology. |
| D．He believes their system does much better in data collection. |
