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Much of the United States is locked by an unusually large winter storm, which has sent temperatures dropping sharply across the country, from coast to coast and as far south as southern Texas. In many areas, ice and snow storms have added to the challenges. Only a few areas in the south have dodged the freezing weather pattern. The National Weather Service（NWS） says that a winter storm, this large and this serious, has almost never been seen before.
The NWS reports that over 150 million Americans were under winter storm warnings. In Texas,over 2.7 million people were left without power on Monday. Texas isn't used to such serious winter weather. In the city of Houston, temperatures have dropped to - 9℃.The storm has led to huge, deadly highway accidents, and has forced its airport to cancel flights. On Sunday, President Joe Biden declared an emergency in Texas, allowing the state to get more help for the weather disaster from the US government. Several other states have declared some sort of weather-related emergency. In Washington and Oregon, warming shelters were opened to help people stay warm and safe.
The NWS says cold air from the Arctic is behind the record-breaking low temperatures. Though it may seem surprising, global warming may be one of the causes. A strong wind known as the jet stream usually flows in a circle around the Arctic, keeping super-cold air near the North Pole. But as the jet stream weakens because of climate change, the cold air is able to escape the Arctic and bring freezing temperatures to places that are normally much warmer.
The NWS is forecasting there'll be more snow and freezing rain over the next few days as a new storm cuts up toward the Northeast from the middle of the country. The NWS says that much of the country will continue to have extremely cold temperatures, and it's likely that hundreds of coldweather records will be broken. Perhaps, people should think about the consequences of global warming.



Which can best replace the underlined word "dodged" in paragraph 1？ ______

A. Seen.
B. Recorded.
C. Avoided.
D. Defeated.

Why does the author mention Texas？ ______

A. It's hit the hardest by extreme weather.
B. It's brought the super cold under control.
C. It's the first to warn of the climate disaster.
D. It's helping other states with the winter storm.

What does paragraph 3 mainly focus on？ ______

A. How the jet stream forms in the Arctic.
B. What causes the extreme cold in America.
C. Why the cold air escapes from the Arctic.
D. When the global warming affects America.

What is the NWS's prediction about the rough weather？ ______

A. It'll change climate permanently.
B. It'll cause another new storm.
C. It'll lessen global warming.
D. It'll go on for some time.

Scientists at MIT have managed to change ordinary spinach （菠菜）plants into natural sensors which can find chemicals used in bombs. The secret to giving spinach these special powers is nanotech （纳米技术），which is scientific area that deals with making or changing things that are extremely tiny.
"Ordinary spinach plants can be found everywhere and easy to store； like other plants, they normally take in carbon dioxide gas," the scientists say. "But actually they can sense small changes of soil and water potential and respond to them. If we tap into this point, there is a wealth of information to access. " That's what the scientists use to power their tiny experiments.
For this experiment,the scientists placed two different kinds of tiny nano-materials into spinach plants. To get them into the plants,the scientists put a liquid containing them on the bottom of the plant's leaves. As part of its natural process,the spinach plant pulls water through its roots and into its leaves. If the water contains certain chemicals used in bombs, the tiny sensors in the leaves make the nano-tubes,which,along with the sensors, were placed into the spinach plant before by the scientists, produce a slightly special kind of light. By watching the plant constantly using a camera attached to a cheap computer,the scientists set up a system that can send a warning email if chemicals from explosives are found in the water.
The computer the scientists used is about the size of a playing card. They say that in the future,their system could even use a cell phone with its camera changed slightly. Discovering chemicals used in bombs is just one of the many uses the researchers are exploring. They have used such plants to discover several other dangerous chemicals as well. From their point of view, there's no doubt that in the future, such systems could give farmers specific information about the health of the land and water on their farms.



Why do the scientists use plants to do the experiment？ ______

A. They are common in the dailylife.
B. They are environmentallyresponsive.
C. They absorb much carbondioxidegas.
D. They are small in size andeasytostore.

What's the function of the carbon nano-tubes placed into spinach plants？ ______

A. To control the camera.
B. To contain the liquid.
C. To fix the tiny sensors.
D. To give off plant light.

What can we say about the application of the experiment？ ______

A. It's diverse.
B. It's unexpected.
C. It's limited.
D. It's cheap.

What's the suitable title for the text？ ______

A. Spinach Is Sensitive to Chemicals in Bombs
B. Spinach Is taught to Send Warning Emails
C. Nanotech Helps Spinach Grow Healthily
D. Nanotech Protects Spinach from Danger

A seismic （地震的；重大的） shift in climate science might be heating up.
New research shows that sound waves produced by earthquakes can be used to measure temperatures in the ocean which traps 90% of the heat Earth absorbs from the sun, making long-term changes in ocean warmth, a major factor in how the world might respond to global warming.
For years the main approach of measuring ocean temperature has been Argo, an array （阵列） of 4000 automatic floats, which drifts the globe, sampling ocean water and measuring its temperature. Yet Argo measurements stop at 2000 meters.
The new technique called "Seismic Ocean Thermometry" would be especially useful in detecting long-term changes in ocean temperatures deeper than Argo's reach.
"Ocean Acoustic Tomography"， the basis for the current research, was first tested nearly 30 years ago. The initial studies created sound waves artificially, basically increasing the volume on giant underwater speakers. Scientists measured the sound's travel time from the speakers to receivers thousands of kilometers away. Because ocean temperatures affect the speed of the waves, the researchers could calculate average temperatures along their paths. But some believed the noise was a threat to ocean life and the technique never took off.
The new study instead uses a natural sound source for investigation： earthquakes making a low, continuous noise beneath the seafloor off the coast of Sumatra that drum up sound waves in the ocean. On the shores of the Chagos Islands in the East Indian Ocean, between 2005 and 2016 Seismic Station Diego Garcia recorded seismic waves produced by those earthquakes. Some of those waves created physical changes in land and sea as they traveled. Others were sound waves or T waves that moved through the deep ocean, delivering valuable data about ocean temperature.
12 years of data coupled with mathematical models pointed to a temperature change of roughly 0.044 degrees per decade, a trend larger than those predicted by Argo. The findings suggest that Seismic Ocean Thermometry is a feasible method to measure changes in ocean temperature, Further data from other regions of the globe and other timeframes would help improve the warming models and predictions.
And in future studies the researchers plan to listen directly for sound waves, using a network of hydrophones, microphones which detect sound waves under water. Sound waves set the tone for a deep dive into our warming oceans even if they fail to reach 60000 miles under the sea.



What disadvantage does Argo have？ ______

A. Its reach is limited.
B. It takes long to collect samples.
C. It doesn't work globally.
D. Its prediction isn't reliable at all.

It can be learned that Ocean Acoustic Tomography ______ .

A. was tested many times but never succeeded
B. remained unpopular for fear of potential harm
C. was assumed to be too complicated to be controllable
D. measured ocean temperature just as the new research does

It can be inferred from the new findings that ______ .

A. some warming is working its way deeper into the ocean
B. ocean temperature is rising faster owing to earthquakes
C. sound travels faster in colder water than in hotter water
D. sound waves will slow down the warming of the ocean

Which is the best title for the passage？ ______

A. Sound Waves First Applied to Climate Science
B. New Factors Found to Be Heating up the Ocean
C. A Natural Approach Holding Back Global Wanning
D. Ocean's Hidden Heat Measured with Earthquake Sounds

The term modern art sounds like it means art that is popular at the moment, but in fact, modern art is a style that originated over 150 years ago, and includes artists that by now have attained classic status, such as Picasso, Matisse, and Gauguin. And what's even more ironic（讽刺的） is that the movement they pioneered, considered revolutionary at the time, was inspired largely by an object of a traditional and ancient design.
As far back as the Renaissance, the primary European art movements emphasized conventional representation and adherence （遵循） to classical forms. But that began to change in the late 19th century as artists like Van Gogh and Cezanne expanded the boundaries of painting. Soon, a movement arose that sought to create an entirely new style of art, and one way of doing so was to look beyond Western civilization.
Henri Matisse showed his friend Picasso a mask he had acquired made by the Dan tribe of the Ivory Coast. The mask awoke Picasso's curiosity, leading him to visit the Trocadero Ethnographic Museum in Paris in 1907. The visit was eye-opening for Picasso, who declared that African masks were what painting was all about. At this time, Picasso had been working on a painting of five naked women in a style that would later come to be known as Cubism. And while three of these ladies show facial features found in ancient Iberian art,a nod to Picasso's Spanish heritage, the faces of the two on the right closely resemble African masks. Created in 1907 after hundreds of sketches and studies, "Les Demoiselles d'Avignon" has been considered the first truly 20th century masterpiece, breaking with many previously held notions in art.
Inspiration from ancient cultures started one of the most revolutionary movements in art history, but were these artists playing the role of explorers or conquerors, stealing ideas and profiting from cultures they considered primitive？Questions like this deserve scrutiny（审查），as artists continue to redefine standards. Perhaps not too long from now, the bold innovations（单新）of modern art will be overturned by a new set of pioneers drawing inspiration from another unlikely source.



The style of European art didn't experience any changes until ______

A. artists turned to nature for inspiration.
B. artists looked beyond western civilization.
C. artists began to emphasize self-expression.
D. artists expanded the boundaries of painting.

What can we learn about "Les Demoiselles d'Avignon"？ ______

A. It combined different cultural elements.
B. Its distinctive style invited much criticism.
C. It broke away from all conventional styles.
D. It was inspired by a visit to the Ivory Coast.

What does the author try to convey in the last paragraph？ ______

A. Artistic creation involves imitation and innovation.
B. The pioneering role of modern artists is questionable.
C. Drawing inspiration from different cultures is essential.
D. It's vital that the standards of art should change constantly.

What is the best title for the text？ ______

A. A Glimpse into Modern European Art
B. The Pioneering Figures of Modern Art
C. Why We Should Redefine Modern Art
D. How Ancient Art Influenced Modern Art

Fairy tales focus on creating a fantasy world to the reader encouraging imagination and teaching problem-solving skills. It is equally important that they provide influential moral lessons, highlighting the dangers of failing to follow the social codes that let human beings coexist in harmony. Such moral lessons may not mean much to a robot, but a team of researchers at Georgia Institute of Technology believes it has found a way to use the fairy tales as moral lessons that AI （artificial intelligence） can take to its cold and mechanical heart.
The collected stories of different cultures teach children how to behave in socially acceptable ways with examples of proper and improper behavior in fairy tales, novels and other literature. We believe story comprehension in robots can eliminate the immoral behavior of the the intelligent robots, which was predicted and feared by some of the biggest names in technology including Stephen Hawking and Bill Gates. This system is called "Quixote" （堂吉诃德）. It collects story plots from the Internet and then uses those stories to teach robots how to behave.
The experiment done by the designers involves going to a drugstore to purchase some medicine for a human who needs to get it as soon as possible. The robot has three options. It can wait in line； it can interact with the store keeper politely and purchase the medicine with priority； or it can steal the medicine and escape.
Without any further directives（指令）， the robot will come to the conclusion that the most efficient means of obtaining the medicine is to steal it. But Quixote offers a reward for waiting in line and politely purchasing the medicine and a punishment for stealing it. In this way, the robot will learn the moral way to behave on that occasion.
Quixote would run best on a robot that has a very limited function. It's a baby step in the direction of teaching more moral lessons into robots. We believe that AI has to be trained to adopt the values of a particular society, and in doing so, it will strive to avoid unacceptable behavior. Giving robots the ability to read and understand our stories may be the most efficient means.



What is the robot really expected to do in the experiment？ ______

A. To purchase some medicine for a human.
B. To finish the task as efficiently as possible.
C. To perform in a socially acceptable way.
D. To perform under the designer's instructions.

What does the underlined word mean？ ______

A. Praise.
B. Promote.
C. Rid.
D. Strengthen.

Which of the following information can we get？ ______

A. Quixote has already been widely used in robots.
B. Robots will be definitely designed with limited function.
C. The development of robots is still in a baby step.
D. Robots are necessarily to be trained to follow social codes.

What's the text mainly about？ ______

A. Using stories to teach moral to robots.
B. Speeding up the development of robots.
C. Preventing robots from behaving badly.
D. Training robots to read fairy tales.

While the arts can' t stop the COVID-19 virus or the social unrest we see in the world today, they can give us insight into the choices we make when moving through crises and chaos. The arts invite everyone to think in new ways.
We often experience works of art as something that's pleasing to our senses without a full understanding of the creative effort. Great art often shows us contradictions and crises, and we can learn a great deal from their resolutions（解决）. Through our understanding of art, we can gain a deeper understanding of how we might overcome our own challenges. In understanding extremes of contrast, we can see the beauty in art with themes that are not simply pleasing for their magnificent features or qualities.
Beethoven offers a wonderful example of moving artfully through crises and chaos. He composed his Symphony No. 9 as his hearing loss became more and more pronounced. The opening of the symphony seems to come out of nowhere, from near silence in the opening to a full expression of what many consider to be the joy of freedom and universal brotherhood with Schiller's Ode to joy（欢乐颂）. Beethoven appears to have created a work of art that not only freed him from his personal struggles, but one that also speaks to the joy of living together in peace and harmony.
Have a dialogue between the two opposing parts and you will find that they always start out fighting each other until we come to an appreciation of difference-a oneness of the two opposing forces. The arts offer many lessons that can help us gain the knowledge we need to move more confidently in today's competitive and uncertain environment. An openness to arts-based solutions will give you more control over your future.



What value does art have beyond pleasing people's senses？ ______

A. It brings people inner peace.
B. It contributes to problem-solving.
C. It reduces the possibility of crises.
D. It deepens understanding of music.

What can we learn about Beethoven's Symphony No. 9？ ______

A. It celebrates freedom and unity.
B. It aims to show crises and chaos.
C. It opens with Schiller's Ode to Joy.
D. It is unfinished due to his hearing loss.

What is the author's suggestion on dealing with conflicting forces？ ______

A. Leaving things as they are.
B. Making a choice between them.
C. Separating them from each other.
D. Engaging them in a conversation.

Which of the following can be the best title for the text？ ______

A. How COVID-19 changes art
B. Essentials of Symphony No. 9
C. Moving artfully through crises
D. Joy in the eyes of Beethoven

Baby foods on market generally contain too much sugar, causing a source of health concern, a new report by World Health Organization （WHO） says.
The United Nations specialized agency on public health based the conclusion on an examination by its European office of about 8，000 baby food products on shelf between. November 2019 and January 2020. It warns that the very high level of sugars present in commercial products is a cause for concern. They increase the risk of overweight and teeth holes while causing a lifetime eating habit in favor of sugary foods.
"In around half of the products examined,more than 30 percent of calories were from total sugars and around a third of products contained added sugar or other sweetening agents," the world health body said in the report released on Monday to update guidelines for babies' diets. The examination that covered more than 500 stores in Austria, Bulgaria, Israel and Hungary also finds the labels of up to 60 percent of the inspected food are misleading consumers by claiming to suit babies under six months old.
In the report,countries are advised to make new laws on controlling high sugar intake,ban added sugars and sweeteners in baby foods, and put an end to the promotion of breast milk substitutes. It also requires labels on candies and sweetened drinks, including fruit juices and condensed（压缩）milk, to state they are not suitable for children under three. Meanwhile, WHO recommends that children between six months and two years be fed nutrient-rich home-prepared foods.
"WHO has long recommended that babies receive only breast milk for the first six months of life. Good nutrition in babyhood and early childhood remains the key to ensuring best child growth and development, and to better health outcomes later in life," said Zsuzsanna Jakab,WHO regional director for Europe,in a statement.



How did WHO get the finding？ ______

A. By testing baby foods' flavour.
B. By examining some baby foods.
C. By monitoring baby foods' production.
D. By conducting an interview about baby foods.

What can we know about the 500 stores？ ______

A. Some of them are selling poor baby foods.
B. They have broken the laws about baby foods.
C. Their baby foods have damaged babies' health.
D. They are taking action to change the present situation.

What is a key to handling the concern？ ______

A. The experts' guidance.
B. The consumers' cooperation.
C. The stores' being closed down.
D. The government's involvement.

What food does WHO suggest for children under half a year old？ ______

A. Condensed milk.
B. Fruit juice.
C. Breast milk.
D. Home-prepared foods.

It's no secret that inhaling（吸入）smoke is bad for your lungs. But now,scientists are suggesting smoke may also carry and spread infectious diseases. The theory, published in Science Magazine, is based on the research that found wildfire smoke is full of thousands of species of microorganisms（微生物）.Some of these microorganisms, including bacteria and fungal spores（真菌抱子）are known to cause disease.
The new research suggests that when a wildfire burns plants or animal matter and disturbs soils,it exposes thousands of species of bacteria and fungi that otherwise might not easily become airborne. You might think the high heat from fire would kill these organisms,but one study mentioned in the article found that some bacteria even multiply after fires. Scientists say the organisms stick with smoke particulates（颗粒物），allowing them to travel thousands of miles across continents.
Dr. Peter Chen,director of the Division of Pulmonary and Critical Care Medicine at Cedars-Sinai Medical Center in Los Angeles, is interested in the theory but somewhat skeptical that the microorganisms in smoke would actually cause infections. Many bacteria and fungi don't cause lung infections,says Chen,but it's certainly possible that a significant number could worsen symptoms in someone with a preexisting lung condition. "I always thought it was the particulates in smoke that were causing these issues," says Chen."But when I read this,I started thinking,could it be the microorganisms that are also worsening existing illnesses？"
Whether the microorganisms in smoke actually cause infections or simply worsen potential respiratory（呼吸的）issues, the article raises a new health threat that is "certainly alarming"， says Kelsey Jack, an associate professor of environmental and development economics. This is especially true for lower-income populations, Jack says, because people with fewer protective means are often more exposed to the environment. If smoke is affecting the air quality in a certain area, the people who work outside, or who have to go to the office on foot or by bike will inhale more smoke than those who drive.
But until more research is done,Chen says the best thing people can do is just follow existing recommendations when air quality is poor-including staying indoors, keeping windows and doors closed, using HEPA filters and running air conditioning.



What can we know about the microorganisms from Paragraph 2？ ______

A. Some could reproduce after fires.
B. They could be killed by high heat.
C. They could possibly travel through air by themselves.
D. Some could copy the smoke particulates.

How do most microorganisms affect people according to Dr. Peter Chen？ ______

A. They will cause lung infection.
B. They might worsen lung diseases.
C. They will destroy living environments.
D. They might damage respiratory systems.

Why are lower-income people suffering more than others according to Kelsey Jack？ ______

A. They live in poor areas.
B. They drive to and from work.
C. They have suffered from lung disease.
D. They are exposed to polluted air more frequently.

What does Chen advise people to do in the last paragraph？ ______

A. To wait for the results of more researches.
B. To ignore the air quality and to work out outdoors.
C. To follow previous suggestions on dealing with poor air quality.
D. To avoid using filters and air conditioning.

Range anxiety（里程焦虑）， the fear of running out of power before being able to recharge an electric vehicle, may be a thing of the past, according to a team of Penn State engineers who are looking at lithium iron phosphate batteries（磷酸铁锂电池）that have a range of 250 miles with the ability to charge in 10 minutes.
"We developed a pretty clever battery for mass-market electric vehicles," said Chao-Yang Wang, a professor and director of the Electrochemical Engine Center at Penn State. "There is no more range anxiety and this battery is affordable". The researchers also say that the battery should be good for 2 million miles in its lifetime.
They report today in Nature Energy that the key to long-life and rapid recharging is the battery's ability to quickly heat up to 140 degrees Fahrenheit, for charge and discharge, and then cool down when the battery is not working.
The battery uses a self-heating approach previously developed in Wang's center. The self-heating battery uses a thin nickel foil（镍箔）with one end attached to the negative terminal and the other extending outside the cell to create a third terminal. Once electrons flow it rapidly heats up the nickel foil through resistance heating and warm the inside of the battery. Once the battery's internal temperature is 140 degrees F， the switch opens and the battery is ready for rapid charge or discharge.
"This battery has slenderized weight, volume and cost," said Wang. "I am very happy that we finally found a battery that will benefit the mainstream consumer mass market." According to Wang,these smaller batteries can produce a large amount of power upon heating-40 kilowatt hours and 300 kilowatts of power. An electric vehicle with this battery could go from zero to 60 miles per hour in 3 seconds and would drive like a Porsche, he said. "This is how we are going to change the environment and not contribute to just the luxury cars," said Wang. "Let everyone afford electric vehicles."



Which can best describe the battery in the text？ ______

A. Cheap and heavy.
B. Costly but beneficial.
C. Expensive but small-sized
D. Affordable and efficient.

Why can the battery be used for long and charged so fast？ ______

A. It is environmentally friendly.
B. It heats up and cools down rapidly.
C. It helps speed up the car instantly.
D. It charges when it doesn't work.

What does Paragraph 4 mainly talk about？ ______

A. How the battery works.
B. Advantages of the battery.
C. How the battery is produced.
D. Applications of the battery.

The underlined word " slenderized" in Paragraph 5 can probably be replaced by ______ .

A. promoted
B. gathered
C. combined
D. reduced

At a large forest park in eastern Beijing, 11 birds on the state-level protection list were recently released.
These birds had recovered after the Beijing Wildlife Rescue and Rehabilitation Center rescued and took care of them. "We will speed up our efforts to push the establishment of district-level wildlife rescue centers to jointly guard the health of wildlife," said Du Lianhai, director of the center.
The center was set up in 2001 and built a wildlife rescue base in the capital's Shunyi District in 2005. Staff at the base have rescued and rehabilitated over 30，000 wild animals in total.
Wildlife protection has been strengthened in Beijing in recent years. On June 1，the city's newly adopted regulation on wildlife protection took effect, introducing stricter and more concrete measures to protect the environment and wildlife.
For example,the regulation states clearly that Beijing bans hunting throughout the year,compared with the previous regulation which bans hunting during the periods of March to May and September to November each year. The new regulation also gives severer punishment for poachers.
After years of monitoring,data with the Beijing Gardening and Greening Bureau recently showed ecological reconstruction progress. The species and quantity of wild animals in Beijing are continuously increasing,with the number of terrestrial spinal wild animals （陆地脊椎野生动物）growing from 461 species in 1994 to more than 500. The habitat of the endangered bird has expanded from Fangshan District to the whole city, according to the bureau.
"The enforcement of the new regulation marked a new phase in Beijing's wildlife protection work," said Dai Mingchao, deputy director of the Beijing Gardening and Greening Bureau.
"We will step up the publicity of the regulation and raise citizens' awareness of wildlife protection," Dai said. "In our integrated protection of mountains, rivers, forests, farmlands, lakes and grasslands,we take into full consideration the requirements of food-chain construction, ecological corridor construction,and wildlife and their habitat protection."



In writing Paragraph 1， the author aims to ______ .

A. introduce the topic
B. present an argument
C. reach a conclusion
D. describe a place

What have staff at the wildlife rescue base done？ ______

A. They have sped up their efforts to recover the birds.
B. They have guarded people's health against danger.
C. They have saved wild animals from a dangerous situation.
D. They have pushed the establishment of district-level wildlife rescue centers.

What does the underlined word "concrete" in Paragraph 4 probably mean？ ______

A. Practical.
B. Temporary.
C. Effective.
D. Specific.

What do we know about the new regulation？ ______

A. It is mainly targeted at poachers.
B. It is the first such regulation in Beijing.
C. It takes many years to come into being.
D. It prohibits people from hunting in Beijing all the year.

What can we learn from Paragraphs 7 and 8？ ______

A. Beijing citizens are still not familiar with the new regulation.
B. After taking the new regulation, Beijing will enter a new phase.
C. They rarely give full consideration to the requirements of food-chain construction.
D. The protection of mountains, rivers, forests, farmlands, lakes and grasslands are not in the new regulation yet.

What could be the best title for the passage？ ______

A. How to protect wild animals in Beijing
B. Beijing steps up wildlife protection with new regulation
C. More district-level wildlife rescue centers established in Beijing
D. Wildlife protection has been strengthened in Beijing