【推荐1】Someday, you may no longer need to brush your teeth by hand. Instead, a group of billions of nanoparticles (纳米粒子) could automatically do all that work for you. It would be especially life-changing for people who find it difficult or impossible to hold and move a toothbrush.

Steager, an engineer at the University of Pennsylvania (Penn) in Philadelphia and Hyun Koo, an inventor and dental researcher there, found a way to form the nanoparticles into long, skinny bristles (刷毛), a lot like the ones on a toothbrush. But these bristles shape-shift to fit whatever surface they encounter.

The tooth-cleaning robot works thanks to two magnets (磁铁). One goes each side of the teeth. The nanoparticles sit in a liquid between the magnets. When the magnets are turned off, the nanoparticles move randomly in the liquid. As soon as one magnet gets turned on, the nanoparticles gather together near its center. When the researchers turn on the other magnet and turn off the first one, the nanoparticles extend outward in long, skinny bristles When there’s a tooth in the way, these bristles can’t stretch out as far as they want. So they push against the tooth’s surface. If there’s a gap between teeth, they push into the gap. Moving the magnets makes the bristles move against and between teeth. All that motion cleans the teeth. As a bonus, the nanoparticles also have strong power to kill viruses.

The new device is just a proof of concept The researchers still need to turn it into a product that people will want to use. “There’s a lot of engineering to get from here to there, but every good idea needs to have a start.” says Steager.

1. What is special about the tooth cleaner?

A．It’s water-proof.	B．It’s transformable.
C．It looks like a toothbrush.	D．It contains skinny bristles.

2. What is Paragraph 3 mainly about?

A．The working principle.	B．The magnets motion.
C．The virus-killing process.	D．The bristles formation.

3. How does Steager feel about the future of the device?

A．Uncertain

B．Confident

C．Concerned

D．Surprised.

4. Which of the following would be the best title?

A．A Tooth-Cleaner Fighting Bacteria	B．A Breakthrough in Medicine
C．A Shape-Shifting Robotic Tooth-Cleaner	D．A New Concept for a New Start

【推荐2】Faced with a decreasing population and workforce, Japan has been increasingly turning to robots for help. Over the years, the robots have carried out a large number of human tasks, including building products and providing care for the elderly.

However, the robots currently being used by companies, like Walmart and Amazon, are only able to perform single, repetitive tasks, such as packing boxes. Model-T, on the other hand, has a wider range of movement and is able to hold, pick and place objects of several different shapes and sizes into different locations, making it ideal for convenience and grocery stores, which sell a large variety of items.

Model-T robots are operated from a distant location by human “pilots” wearing a virtual reality (VR)headset and special gloves, which allow them to feel the product the robot is holding in their hands and guide it to the right shelf.

The VR-controlled robots are ten times cheaper than automated robots, because they don’t require advanced programming and are easier to develop and maintain. And their easy-to-use controls require little training. Tomohiro Kano, a general manager in charge of development at FamilyMart, believes this will enable the chain to hire workers who would typically not work in stores.

Though Model-T appears to be getting rapidly through the experiments, it is not quite ready to enter the workforce. Besides being a lot slower than humans, it is also only able to lift packaged items, and cannot get hold of things such as fruits and vegetables. The company is working to improve the weaknesses and hopes to introduce a faster, more skillful Model-T within the next two years. They believe that in addition to the stores, the robots could also be useful in hospitals, allowing doctors to do operations from remote locations.

1. What is one of the features of Model-T according to the text?

A．It works much faster than humans.

B．It can easily hold all kinds of objects.

C．It can be operated from a distance away.

D．It is harder to produce than an automated robot.

2. What does the underlined word “this” in paragraph 4 refer to?

A．The low price of Model-T.	B．The easiness to operate Model-T.
C．The low-level programming of Model-T.	D．The strict training for maintaining Model-T.

3. What can we infer from the last paragraph?

A．Model-T is now being massively produced.

B．Japan’s workforce will be reduced by Model-T.

C．The weaknesses of Model-T have been overcome.

D．Model-T may be used in wider fields in the future.

【推荐1】As a foreigner , I often hear the Chinese calling me laowai ” . If I could not speak Chinese or if I had no understanding of Asian customs , I might be angry when I am called a “ laowai ” . But having lived in the Philippines and China’s Taiwan Province teaching English for several years , I have come to China with a different view from most other foreign teachers here . In such situations , I just answer back in standard Chinese : “ Ni zenmo zhidao wo shi waiguoren ?( How do you know I’m a foreigner ? )” When I hear people shout out “ hello ” in a more impolite way and then laugh , I reply in Chinese with “ Ni de yingyu bi wo de hao .(Your English is better than mine .)”

Speaking Chinese is a way of living an easier life in China . As an English teacher at Hubei University in Wuhan , I was once invited by a student to spend the weekend with his family . Because I can speak Chinese quite freely , I was able to talk with my student’s entire family . From my personal experience , I knew that the Chinese have a “ gift ”for making foreigners in China feel right at home . That fun-filled weekend I spent with my student’s family in Caidian , a small suburb of Wuhan , just showed that my idea was right . It was an experience I will never forget .

Americans have a saying : If you can’t beat them , then join them .The secret to feeling at home with the Chinese people isn’t to try to make them change over to Western ways . The secret is to become one of them . Just go with the flow , or don’t take things too seriously . In this way you will surely feel at home in China .

If you no longer emphasize (强调) our differences from the Chinese , you will be more willing to concentrate on what “ big noses ” and “ small noses ” have in common .

1. The reply “Ni de yingyu bi wo de hao ” shows _______ .

A．the author really think so	B．the author isn’t angry
C．the author likes to talk with the Chinese	D．the author likes to speak Chinese

2. Which of the following is NOT true ?

A．The author has known Chinese customs fairly well .

B．The author is difficult to get along with .

C．The author doesn’t mind being called a “ laowai ” .

D．The author can speak Chinese very well .

3. Shouting out “ hello ” to a strange foreigner is usually considered _ by foreigners .

A．rude

B．curious

C．friendly

D．brave

4. The phrase “ go with the flow ” here means _______ .

A．feel at home	B．take things easy
C．flow with the river	D．when in Rome , do as the Romans do

【推荐2】Getting rid of dirt, in the opinion of most people, is a good thing. However, there is nothing fixed about attitudes to dirt.

In the early 16t century, people thought that dirt on the skin was a means to block out disease, as medical opinion showed that washing off dirt with hot water could open up the skin and let ills in. A particular danger was thought to lie in public baths. By 1538, the French king had closed the bath houses in his kingdom. So did the king of England in 1546. Thus began a long time when the rich and the poor in Europe lived with dirt in a friendly way. Henry IV, King of France, was famously dirty. Upon learning that a nobleman (贵族) had taken a bath, the king ordered that, to avoid the attack of disease the nobleman should not go out.

Though the belief in the benefits of dirt was long-lived, dirt has no longer been regarded as a nice neighbor ever since the 18th century. Scientifically speaking, cleaning away dirt is good to health. Clean water supply and hand washing are practical means of preventing disease. Yet, it seems that standards of cleanliness have moved beyond science since World War II. Advertisements repeatedly sell the idea: clothes need to be whiter than white, cloths ever softer, surfaces to shine. Has the hate for dirt, however, gone too far?

Attitudes to dirt still differ hugely nowadays. Many first-time parents nervously try to warn their children off touching dirt, which might be responsible for the spread of disease. On the contrary, Mary Ruebush, an American immunologist (免疫学家), encourages children to play in the dirt to build up a strong immune system. And the latter position is gaining some ground.

1. The kings of France and England in the 16th century closed bath houses because ________.

A．they lived healthily in a dirty environment

B．they thought bath houses were too dirty to stay in

C．they believed disease could be spread in public baths

D．they considered bathing as the cause of skin diseases

2. Which of the following best describes Henry IV’s attitude to bathing?

A．Afraid.

B．Content.

C．Supportive.

D．Uninterested.

3. How does the passage mainly develop?

A．By providing examples.	B．By making comparisons.
C．By following the order of time.	D．By following the order of importance.

4. What is the author’s purpose in writing the passage?

A．To stress the role of dirt.	B．To introduce the history of dirt.
C．To call attention to the danger of dirt.	D．To show the change of views on dirt.

【推荐3】After waking up, you may feel upset that you cannot recall the dreams you had last night. Artificial intelligence (AI) may be able to help.

Previously, there have been AI models that can turn text into images. They can do this by learning from a large amount of data from both tests and images. This time, researchers from Osaka University in Japan have trained an AI system called Stable Diffusion to re-create images based on people’s brain scans (扫描) reported Science magazine.

The researchers used an online data set provided by the University of Minnesota, US, which consisted of brain scans from four participants as they each viewed a set of 10,000 photos. The scans were recorded by functional magnetic resonance imaging (FMRI) (磁共振现象).

The AI then learned about the brain activities by analyzing changes in blood flow shown by the FMRI data --- when a part of the brain is activated, more blood will flow to it. It then matched the brain activities with the photos. Through this method, AI learned how human brains would react when seeing different photos.

Finally, the researchers tested the AI on additional brain scans from the same participants when they viewed photos of a toy bear, airplane, clock and train. If the person looked at an airplane, for example, the AI would use the brain scan data to create an image of a very blurry airplane. Then, it would turn on the previous “text-to-image” model and improve the quality of the image by feeding itself the keyword “airplane”. The final images were “convincing” with about 80 percent of accuracy, according to the researchers.

The new study created a novel approach that incorporates texts and images to “decipher (解读) the brain”, Ariel Goldstein from Princeton University, US, told Science magazine. In the future, scientists hope that the technology can be used to record imagined thoughts and dreams or allow people to understand how differently other animals perceive reality.

1. What is Stable Diffusion mean to do?

A．Scan people’s brains.	B．Turn texts into images.
C．Use brain scans to rebuild images.	D．Record relevant experimental data.

2. How did the Al learn about the participants’ brain activities?

A．By analyzing changes in blood flow.	B．By asking the participants questions.
C．By comparing different brain scans.	D．By referring to previous Al models.

3. What does Ariel Goldstein say about the technology?

A．It has been adopted in many countries.	B．Its development is far from satisfactory.
C．It is lacking in convincing evidence.	D．Its application has a great prospect.

4. What is the best title for the text?

A．AI knows brain scan data of participants.

B．AI learns the reaction of human brains.

C．AI changes text into images with the help of FMRI.

D．AI uses brain scans to re-create images people see.

【推荐1】A doctor named Chepurnov from Siberia conducted a controversial coronavirus immunity test after surviving COVID-19 in March. The 68-year-old Russian doctor spent time with coronavirus-positive patients without wearing a mask to see if he could get a second COVID-19 infection. The doctor was infected a second time and experienced a worse COVID-19 case than he had previously.

This unusual coronavirus immunity test can easily be filed under the “only in Russia” section of COVID-19 news. Only in Russia was a coronavirus vaccine approved for mass use before any scientific research was shared with the world and before the drug cleared the Phase 3 trial. The story gets even crazier, considering the doctor’s age. At 68-years-old, Alexander Chepurnov happens to be the kind of COVID-19 patient most at risk of developing a severe case.

Even so, Chepurnov’s controversial experiment isn’t without worth. It’s certainly the kind of experiment that others wouldn’t necessarily approve of, especially in western countries. But it’s the kind of experiment that can yield results — and Chepurnov did get his wish. He was reinfected with COVID- 19 within six months from the first bout. Chepurnov and his research team started to monitor his antibodies. He discovered that they vanished after three months. “The observation showed a fairly rapid decrease,” he told the paper. “By the end of the third month from the start of the disease, they ceased to be determined.” This falls in line with other studies about COVID-19 antibody life.

Chepurnov’s story also seems to fall in line with other studies that say immunity can last for at least 5-7 months. The story also proves that immunity lasts even after the antibodies are gone and suggests that other immune system components are indeed involved in providing prolonged protection. Others theorized that T cells would extend immunity beyond the life of the first batch of antibodies. Chepurnov’s empirical findings are also important for vaccine research. If immunity lasts less than a year, more booster shots (加强针剂) might be needed after the initial doses.

But Newsweek points out a problem with the experiment. Because his first case of COVID-19 hasn’t been diagnosed via a PCR test. Also, Chepurnov’s experiment hasn’t been published in a scientific journal, and it’s unclear what scientific rigors were applied. Still, if his findings are accurate, Chepurnov is actually right to warn against using a herd immunity approach to beat the pandemic.

1. Why is Chepurnovs experiment considered controversial?

A．Its not effective.	B．Its too dangerous.
C．Its disapproved of by Russia.	D．Its not diagnosed via a PCR test.

2. What does the underlined word "they" in Paragraph 3 probably refer to?

A．diseases

B．viruses

C．antibodies

D．results

3. What is the finding of Chepurnovs experiment?

A．COVID-19 immunity lasts permanently in ones body.

B．The longevity of COVID-19 antibodies is about 3 months.

C．Old patients are most at risk of developing a severe COVID-19.

D．Vaccination can protect one from being infected with coronaviruses.

4. Whats the main idea of the passage?

A．Siberia is a unique place for treating COVID-19 patients.

B．Newsweek found the evidence against herd immunity to COVID-19.

C．Researches showed humans produce antibodies if infected with coronaviruses.

D．A controversial experiment on coronavirus immunity was conducted in Russia.

【推荐2】Pang Hui placed a few more pairs of chopsticks on the table for a family dinner, though she did not expect her big family of seven would use them as serving chopsticks.

Surprisingly, her 75-year-old father, who used to shrug off the idea of serving chopsticks, became a firm supporter this time, said Pang, 40, from Beihai, a coastal city of South China's Guangxi Zhuang Autonomous Region.

Chinese people often share dishes, and diners use their own chopsticks to serve themselves food from the shared dishes, a tradition now being challenged by the outbreak of novel coronavirus.

“We feel a sense of crisis as well as the urge to desert our old habits when we see reports of family infections,” Pang said; pointing to the reports of the virus spreading via droplets (飞沫) and close contact.

Local governments are helping to encourage a shift, too. On Feb 10, local authorities of Beihai started a campaign promoting serving chopsticks and spoons, which will avoid cross-infections caused by the use of personal chopsticks.

Similar measures were also adopted in other cities like BeiJing, Shanghai and Hangzhou. Taizhou city in east China's Jiangsu Province even standardized the colours of serving chopsticks and spoons to help diners differentiate (区分) them from personal ones.

The government is also targeting the practice of eating wild animals, which remains present in certain areas.

China stopped the illegal trading and transportation of wild animals shortly after the outbreak.

The move became a permanent ban on Feb 24, when the country made a decision on thoroughly prohibiting (禁止) the illegal trading of wildlife and the consumption of wild animals.

Li Bo, with the Hainan International Center for Wildlife' Protection, said wild animal consumption could lead to the faster extinction of particular species, damage the ecological balance and harm people's health.

“The epidemic (流行病) could become a turning point to eliminate the bad habit,” Li said.

1. What can we learn about Pang Hui’s family from the text?

A．Usually more than seven people dine together.

B．They have started to use serving chopsticks at table.

C．Pang Hui’s father opposes using serving chopsticks.

D．They don't know how to avoid being infected by the virus.

2. According to the text, what has been done by the government?

A．Sharing dishes has been abandoned.

B．Cross-infections have been prevented.

C．Eating wild animals has been forbidden.

D．Standard personal chopsticks have been adopted.

3. What does the underlined word "eliminate" in the last paragraph probably mean?

A．Explain.	B．Discover.
C．Form.	D．Remove.

4. What can be the best title for the text?

A．Serving Chopsticks Promoted	B．Ways to Help People Stay Healthy
C．Corona virus Leads to Change	D．China Bans Trading of Wildlife

【推荐3】What is a hero? We may think of the fictional characters with supernatural powers or great people who can influence world events. Now, as the nation continues its all-out efforts to fight against the novel coronavirus pneumonia (新冠肺炎), medical staff have become heroes in the eyes of the public.

As of Feb 19, a total of 32, 000 medical staff outside Hubei province have been working to treat patients around the center of the outbreak.

Zhang Dingyu, the president of Wuhan Jinyintan Hospital, is one of these heroes, since the hospital received the first seven patients in December, Zhang has been so busy that he barely gets any sleep. Even suffering from amyotrophic lateral sclerosis (肌萎缩侧索硬化), the 56-year-old doctor is doing his best to quicken his pace to save precious time for infected patients.

“I have to run, racing against time to save more patients from the deadly disease, because I don’t have much time left in my life, ” Zhang told Xinhua News Agency.

With the duty of saving lives, many medical professionals like Zhang have been working long hours for days, despite their fear and worries.

Lu Jingjing from Wuhan Children’s Hospital also works at a temporary mobile hospital. She does not let her parents know that she is now working with novel coronavirus-infected patients.

When her parents ask for a video chat, Lu says she is working and lets her husband and children chat with them instead.

“It’s dangerous but we should win the battle with the virus as soon as possible, so that medical staff and patients can go back home, ” she told China Daily.

US writer Khalil Gibran (1883- 1931) once wrote, “Tenderness (温柔) and kindness are not signs of weakness and despair (绝望), but the manifestations of strength and resolution.” It’s true for the medical workers.

Everyone has fear, especially when it comes to deadly diseases. But for medical staff, saving lives comes first and is enough for them to be brave and stay on the front. They may look like ordinary people in daily life, but in these extraordinary (不同寻常的) times, they are heroes.

1. What do we learn from Zhang Dingyu’s words?

A．His illness has turned him into an impatient man.

B．His illness makes him work without any fear.

C．He feels sorry for himself because of his illness.

D．He wants to help as many patients as possible.

2. Why doesn’t Lu Jingjing answer her parents’ video calls?

A．She is too busy and has no time for video chats.

B．She doesn’t want her parents to worry about her.

C．It’s not allowed to make a video call from the hospital.

D．There is no network signal at the temporary mobile hospital.

3. What is the author’s main purpose in writing this article?

A．To explain what makes a modern-day hero.

B．To praise medical staff for their efforts to fight the NCP.

C．To describe what measures China has taken to deal with the virus.

D．To show the difficulties faced by the medical staff treating NCP patients.