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Disease-carrying mosquitoes can spread diseases without affecting themselves. Nearly 700 million people get a mosquito-borne illness each year, which results in over one million deaths. Humans experience continuous pressures from disease-carrying mosquitoes in many parts of the world, so we have to find ways to fight against those insects because they keep getting scarier.
Even though DEET remains the most commonly used,and most powerful,mosquito repellent（防护剂）ever developed,scientists are actively pursuing effective products based entirely on plant oils. While DEET is an effective contact repellent, many people dislike the oily feel and smell on their skin,and sometimes some people are sensitive to it. Consumers are always interested in alternatives to DEET and other synthetic（合成的） repellents, so there are numerous natural repellents on the market.
In my lab at Iowa State University,my team and I have been conducting research on natural products as possible insect repellents for the past 20 years. In the past few years,three of my Ph. D. students have contributed greatly to our research by designing, synthesizing, purifying, characterizing and testing more than 300 closely related chemicals coming from the best of natural repellents like citronellol, menthol and thymol.
These students have successfully tested these repellents against three species of dangerous mosquitoes. The first group of the new repellents act through the air. These chemicals have a vapor action that provides protection. These are potentially most useful in backyards, parks, houses, barracks and horse barns. The other group of the new repellents are the classic ones that stop insects from standing on a treated surface,such as human skin, clothing or tents； some researchers have conducted testing on some humans to confirm the effectiveness and identify the very best ones.
The new repellents were designed and made from the natural materials in plant essential oils. They maintain many of the advantages of the natural repellents：They are fully biodegradable（可生物降解的），with no ecological concerns or environmental wastes,and generally considered safe like the thousands of types of plant essential oils used in the flavor and perfume industries. However,thorough testing will be conducted to determine if they are truly non-poisonous because there is still no enough evidence.



What does the author mainly want to show in Paragraph 1？ ______

A. The way mosquitoes spread disease.
B. The high death rate of mosquito-borne illness.
C. The difficulty of fighting disease-carrying mosquitoes.
D. The urgency of finding tools to fight against mosquitoes

What is a disadvantage of DEET？ ______

A. It causes discomfort to the users.
B. It greatly harms people's health.
C. It can't be applied universally.
D. It won't be effective for long.

What can we learn about the second group of the new repellents？ ______

A. They can kill mosquitoes indirectly.
B. They are mainly used in the open air.
C. They are more effective on human skin.
D. They can prevent mosquitoes from contacting users.

What's the author's attitude to the new repellents？ ______

A. Disapproving
B. Negative
C. Objective
D. Subjective

In the age of online shopping and e-readers, devoted staff and customers keep the doors of Auntie's Bookstore open for 40 years. "When you're in Portland, you go to Powell's Books. When you're in Seattle, you go to Elliott Bay. When you're in Spokane, you go to Auntie's," said John Waite, the owner of the bookstore. "I can't imagine Spokane without Auntie's," he said. "A lot of people can't imagine Spokane without Auntie's, either," Waite said.
Turning visitors into regular customers is important to the store's success. Auntie's markets itself as a destination. A half-dozen book clubs meet there. Most weeks, the store hosts two to four author readings or literary events. "We want people to come down, hang out and experience the feel of having a book in their hands," Waite said.
Eager readers not only want to read books, but want to discuss them, said Kerry Halls, the store manager. Auntie's offers them that chance, she said.
"You can't go to Amazon and talk to someone about your favorite novel, or discuss what you think of the latest Stephen King's book compared with Pet Sematary," she said.
To compete with the convenience of shopping online,Auntie's tries to predict what books will become a trend. They store these books in advance. But Waite doesn't sugarcoat the realities of selling books in the era of Amazon and other online retailers（零售店）. "Even the big guys can't make it," he said,noting physical retailers are striving nationally. As the United States' oldest national bookstore chain,Barnes&Noble has to constantly reorganize to stop the declining sales.
At Auntie's, regular customers are very important to its survival and development. Sales of children's and young adults' books are increasing in recent years. Waite said. "For a long time,older customers have kept bookstores alive," he said. "Now,it's starting to attract younger people." Another reason of Auntie's longevity（长寿） is Northwest culture,which Waite said encourages new ways of thinking and the diversity of ideas. "I think it's a great book town," Waite said. "People are enthusiastic about reading."



What can we learn about Auntie's from Paragraph 1？ ______

A. It is very popular in the local area.
B. It is a highly profitable physical bookstore.
C. It takes full advantage of the e-business platform.
D. It has a longer history than Powell's Books and Elliott Bay.

What is Auntie's goal？ ______

A. To set up a literary environment.
B. To have more regular customers.
C. To awaken people's interest in reading.
D. To encourage readers to learn about more authors.

What does the underlined word "striving" in Paragraph 5 probably mean？ ______

A. Celebrating.
B. Progressing.
C. Struggling.
D. Compromising.

What does the last paragraph mainly talk about？ ______

A. The future of Auntie's.
B. The major customers of Auntie's.
C. The influence of Auntie's.
D. The reasons for Auntie's longevity.

Coral reefs（珊瑚礁）are an integral part of sea life and sustain it by providing shelter and habitat to various organisms. They also supply and recycle nutrients as well as enable a growing fish population, along with other species, for a healthy and diverse ecosystem. However, the rise in average water temperatures due to climate change has resulted in more frequent and longtime "coral bleaching（白化现象）" events that damage their health, causing fish and other sea species to abandon them.
In order to restore this delicate ecosystem, scientists from the UK and Australia conducted a study that involved using loudspeakers underwater near damaged coral reefs to make them sound healthy and attract fish, potentially kick-starting the natural recovery process of coral reefs and their dependent life forms. The location for this experiment was the Great Barrier Reef in the coral Sea, found alongside the east coast of Queensland, Australia. The site is noted to have the largest coral reef system in the world.
"Healthy coral reefs are remarkably noisy places--the crackle of snapping shrimp and the whoops and grunts of fish. Young fish concentrate on these sounds when they're looking a place to settle"， said Steve Simpson, study co-author and a professor at the University Exeter, UK.
By using loudspeakers to copy such sounds, parts of dead coral reefs were found to attract twice as many fish, compared to places where no sounds were played. "These returning fish, are crucial for coral reefs to function as healthy ecosystems. Boosting fish populations in this way could help to kick-start natural recovery processes, preventing the damage we're seeing on many coral reefs around the world," said lead author, Tim Gordon.



What causes the phenomenon of coral bleaching？ ______

A. Diverse species.
B. Noise pollution.
C. Fishing industry.
D. Climbing temperatures.

What approach is introduced to recover the coral reefs？ ______

A. Removing damaged coral reefs.
B. Using loudspeakers to keep fish away.
C. Building new homes for sea species.
D. Playing certain sounds to appeal to fish.

Why are Steve Simpson's words quoted？ ______

A. To provide some findings of the study.
B. To show the progress of the experiment.
C. To explain reasons for the new approach.
D. To give another solution to the problem.

What can we infer from the last paragraph？ ______

A. The attempts are in vain.
B. Natural recovery is impossible.
C. Initial success has been achieved.
D. The coral reefs have returned to normal.

People have different ways of dealing with a common cold. Some take over the counter medicines such as aspirin while others try popular home remedies（治疗） like herbal tea or chicken soup.Yet here is the tough truth about the common cold：nothing really cures it.
So why do people sometimes believe that their remedies work？ According to James Taylor,professor at the University of Washington,colds usually go away on their own in about a week,improving a little each day after symptoms peak,so it's easy to believe it's medicine rather than time that deserves the credit,USA Today reported.
It still seems hard to believe that we can deal with more serious diseases yet are powerless against something so common as a cold.Recently,scientists came closer to figure out why. To understand it, you first need to know how antiviral drugs work.They attack the virus by attaching to and changing the surface structures of the virus.To do that,the drug must fit and lock into the virus like the right piece of a jigsaw（拼图），which means scientists have to identify the virus and build a 3D model to study its surface before they can design an antiviral drug that is effective enough.
The two cold viruses that scientists had long known about were rhinovirus（鼻病毒）A and B. But they didn't find out about the existence of a third virus,rhinovirus C，until 2006. All three of them contribute to the common cold,but drugs that work well against rhinovirus A and B have little effect when used against rhinovirus C.
"This explains most of the previous failures of drug trials against rhinoviruses," study leader Professor Ann C.Palmenberg at the University of Wiscons in Madison,US，told Science Daily.
Now,more than 10 years after the discovery of rhinovirus C，scientists have finally built a highly detailed 3D model of the virus,showing that the surface of the virus is,as expected,different from that of other cold viruses.
With the model in hand,hopefully a real cure for a common cold is on its way. Soon,we may no longer have to waste our money on medicines that don't really work.



What does the author think of popular remedies for a common cold？ ______

A. They are quite effective.
B. They are slightly helpful.
C. They actually have no effect.
D. They still need to be improved.

How do antiviral drugs work？ ______

A. By breaking up cold viruses directly.
B. By changing the surface structures of the cold viruses.
C. By preventing colds from developing into serious diseases.
D. By absorbing different kinds of cold viruses at the same time.

What can we infer from the passage？ ______

A. The surface of cold viruses looks quite similar.
B. Scientists have already found a cure for the common cold.
C. Scientists were not aware of the existence of rhinovirus C until recently.
D. Knowing the structure of cold viruses is the key to developing an effective cure.

What is the best title for this passage？ ______

A. Drugs against cold viruses
B. Helpful home remedies
C. No current cure for common cold
D. Research on cold viruses

Teens and preteens who start the school day really early tend to weigh slightly more than those who start later. That's the finding of a new study of nearly 30，000 Canadians between the ages of 10 and 18. These data are the latest evidence that starting school too early can harm health.
"We know from earlier studies that when school starts too early, kids can't get the sleep they need," says Genevieve Gariepy. She works at Mcgill University in Montreal, Canada. Getting too little sleep can put kids at risk for a number of problems. Sleepy teens are more likely to be over-weight, to have trouble concentrating and to struggle in school. They also are at higher risk of feeling depressed, using alcohol or drugs and getting in car accidents.
As an epidemiologist （流行病学家），Gariepy is interested in patterns of disease. She studies teen obesity, or extreme overweight. In this study, she wanted to know how earlier school start times might be linked to weight.
"Overweight and obesity in adolescents is a big problem in North America," she says. The number of overweight kids has grown over the past 30 years. About one in three U. S. and Canadian teens are now overweight or obese. Kids who don't sleep enough may be at higher risk. So Gariepy decided to find more about the impact of school start times.
Her team collected start times of 362 Canadian schools and found that among "6 to 10" graders, those who started school earlier tended to be slightly heavier for their height. Every 10-minute delay in school start time was linked, on average, to a slightly lower weight among students who were the same sex, age and height. But it's not clear that changing school start time would help heavier kids lose weight. To know for sure, researchers would want to compare the same kids before and after changing to a later school start time.



What is the function of the first paragraph？ ______

A. To show concern for teenagers
B. To introduce the main topic
C. To show the importance of the study
D. To offer advice on school starting time

What does Gariepy want to find out in her research？ ______

A. The links between school start times and teen obesity.
B. How to rid adolescents of being overweight.
C. Why more and more students are becoming obese.
D. The most suitable sleep time for school students.

What can we infer about the study of Gariepy and her team？ ______

A. A 10-minute delay is enough
B. Schools may value its conclusion
C. More work remains to be done
D. Its conclusion is reliable

What can be a suitable title of this text？ ______

A. Experts Worry about the Health of Adolescents
B. Overweight Becomes Common among teenagers
C. Study Links Weight to School Starting Time
D. Students Tend to Sleep Less Than Before

COVID-19 Campus Rules Of UBC Okanagan The rules apply to all students, faculty and staff at UBC's Okanagan campus.
Travel in BC
A Public Health Order for all health regions in British Columbia calls on all individuals,places of work and businesses in BC to significantly reduce social interactions and travel. The current order is in effect until February 1， 2021.
As many are currently making plans for the upcoming Winter Break, all members of the campus community are reminded all non-essential travel should be avoided. The current orders suspend all events and social gatherings to significantly reduce COVID-19 transmission related to social interactions. The order allows for university students to join family for the holidays as this is not considered a social gathering, but it is important to maintain a narrow household bubble.
International travel
If you plan to travel out of Canada during the Winter Break, make sure you are aware of current travel restrictions and are prepared for your trip. Carefully review the updated Travelling to Canada Guide for important information on who is eligible to travel, documents to prepare,ensuring you have health insurance, making a quarantine（self-isolation）plan, and more.
Measurement of body temperature and daily self-assessment when coining to campus
UBC's COVID-19 Campus Rules require that all students, faculty and staff must have their temperatures taken and assess themselves daily for COVID-19 symptoms prior to attending UBC premises. Please use the BC self-assessment tool at /s：//bc. thrive.health/. Anyone experiencing symptoms should follow the guidance provided in the self-assessment tool.
Maintaining physical distancing and wearing non-medical masks
Public Health Orders require all members of our community maintain physical distance and wear non-medical masks. As a reminder, UBC（University of British Columbia） students, faculty, staff and visitors are required to wear non-medical masks, when indoors on our campuses.
Be well, be safe and thank you for following public health and campus rule guidance.



According to the current orders, a university student is allowed to ______ .

A. attend a concert
B. host a party
C. organize a football match
D. get together with his family

What are UBC students required to do when entering the campus？ ______

A. To stand in line.
B. To wear medical masks.
C. To have temperatures taken.
D. To show health insurance.

COVID-19 Campus Rules Of UBC Okanagan were probably posted online ______ .

A. in December
B. in February
C. in August
D. in September

NASA's Artemis program not only hopes to land the next man and the first woman on the lunar south pole by 2024； it also expects them to spend up to seven days in the harsh environment, collecting samples and conducting experiments. To provide future space travelers with a comfortable shelter, two Dutch architects have built a habitat capable of withstanding the Moon's harsh conditions.
The Lanark, designed by Sebastian Aristotelis and Karl-Johan Sorensen of SAGA Space Architects,is made up of a lightweight, aluminum frame that can be efficiently compressed（压缩）for transport to the Moon. Once the astronauts reach their destination, they can easily unfold the mobile home. 328 solar panels on the frame help recharge the battery, ensuring uninterrupted power, while an airtight flexible seam（接缝）protects residents from temperatures as low as -49°F（-45℃）and wind speeds of up to 55 miles an hour.
Though the physical comforts are impressive,even more so are the features dedicated to the astronauts' psychological well-being. A weather simulator that uses solar panels and built-in speakers to create varying weather patterns, like storms, rain, and a sunny day, helps ease the loneliness and weariness of conducting repetitive tasks and looking at the same environment for extended amounts of time.
Aristotelis and Sorenson recently put their creation to test in Moriusaq,Greenland. Located in an isolated region of Northern Greenland,the area boasts hurricane-force winds,temperatures of -22°F（-30℃），and 24 hours of darkness during the winter.
The space architects,who spent two months inside the capsule,tried to simulate（模拟）a lunar mission as much as possible. Their daily meals consisted of coffee, cold protein shakes, and hot soups, all made using powdered ingredients and water defrosted from the surrounding ice.
Aristotelis and Srensen say it exceeded their wildest expectations. "The capsule performed really well-we could sustain a comfortable indoor climate even to the very end of the expedition,which got quite a bit colder and windier than we had expected."



What is NASA's Artemis program designed to do？ ______

A. To send people to the South Pole.
B. To land astronauts on the Moon.
C. To provide space travel for tourists.
D. To supply Dutch residents with the shelter.

What do you learn about The Lunark？ ______

A. It can be moved easily and quickly.
B. It is powered by winds on the Pole.
C. It is used to collect samples on Mars.
D. It was created by NASA scientists.

The weather simulator will contribute to ______ .

A. cleaner air
B. greener plants
C. weaker strength
D. better mental health

Aristotelis and Sorenson chose Moriusaq, Greenland to test the capsule because of ______ .

A. its extreme climate
B. its freezing ocean
C. its mild weather
D. its primitive environment

For many Americans, regular exercise is a complicated commitment-one made at the beginning of January that fades out within weeks or months. Busy work schedules,a lack of motivation and unease towards exercising in public all contribute to the discouraging statistics that only around a quarter of adults exercise enough per week.
This month,enterptiser Trent Ward and designer Yves Behar are uncovering their design for a mirror fitness system,Forme. Forme is reflective like a mirror, uses machine learning to heighten workouts, and offers attachments including ankle belts, rope handles and a heart rale monitor. When not in use, the two arms that form the resistance pulley（滑轮）system fold behind it and the display screen disappears, turning Forme into a simple full-length mirror.
Interest in home exercise has particularly increased recently around the world. Home workout apps have seen a significant uptick in downloads,and trendy brands like Peloton have rolled out free virtual workouts for everyone stuck indoors. One French athlete who was kept away from others chose to run an entire marathon on his 23-foot balcony.
But beyond the new restrictions affecting daily workout routines,Ward and Behar are tapping into the same concerns that have made every home workout appealing： the ability to save time and sweat in the privacy of one's home. In an age of personal metrics（衡量标准）-where one can measure their heart rate and sleep cycles with smart watches and train for marathons with AI smart sneakers-Ward and Behar want to improve exercise through machine leaming. Forme evaluates performance and adjusts weights accordingly. Easy access to performance data also makes it easier to track that progress and stay motivated.
Though it's too soon to tell if mirror gyms will be the trend of the late 2010s to 2020s,Behar explained that having a screen in the home can become the basis for more than just fitness,such as shopping or telemedicine.



What does paragraph 2 mainly focus on？ ______

A. The features of Forme.
B. The ways to operate Forme.
C. The reasons to develop Forme.
D. The theory behind Forme.

How can Peloton benefit its users？ ______

A. By raising their interest in marathon.
B. By offering them online workouts for free.
C. By keeping them far away from others.
D. By entertaining them with all kinds of downloads.

What makes home workout appealing according to paragraph 4？ ______

A. The better results than outdoor activities.
B. The privacy of home.
C. The fresher air at home.
D. The convenient access to mass data.

What is the best title for the text？ ______

A. Can Forme Have More Powerful Functions？
B. Does Regular Exercise Keep up with New Technology？
C. Is the New Trend of Smart Machines at Home Fashionable？
D. Is This AI-powered "Mirror Gym" the Future of Home Exercise？

In an effort to fight the "throw-away culture" and promote reuse and repair, the city of Berlin has taken the unique step of opening its own secondhand department store.
This isn't your grandma's thrift shop （旧货商店）. It resells perfectly good items that would otherwise be thrown away. A pun on the German words for "department store" and "conserving house"， B-Wa（h）renhaus sells a wide variety of products. Far from simply selling old items, the electronic goods have been fixed by expert technicians and come with a year's guarantee. And, to reach more secondhand shoppers, the store was set up right in the middle of the famous Karstadt department store.
With the success of its initial six-month trial run,the city plans to open four more similar operations in other parts of Berlin. By 2030， it hopes to have at least one location in each of Berlin's 12 districts. Since 2008， city policies and educational campaigns have reduced average annual household waste by about 25 pounds per resident. It also recycles about 49% of its mineral construction waste. Currently, the city estimates that 8% of abandoned electronic goods and 6% of huge items thrown away can actually be reused. The goal is to expand the market for these items beyond the usual bargain hunters and eco-conscious consumers.
"Three years ago, we started collecting all kinds of used goods," city spokesperson Dorothee Winden said. "There are lots of things that are well-preserved and functioning but aren't being used anymore. The goal is to give these things a new life with somebody who can use them." The store also includes an education center to encourage more sustainable lifestyles - and also gave an award to a project that recycles school uniforms, so that parents don't have to buy new ones every year.



Why has Berlin opened its own secondhand department store？ ______

A. To attract more shoppers.
B. To promote recycling.
C. To foster traditional culture.
D. To expand secondhand market.

In which aspect is B-Wa（h）renhaus different from the traditional thrift store？ ______

A. The variety of the goods.
B. The location of the store.
C. The quality of the products.
D. The operation of the store.

What can we infer from Paragraph 3？ ______

A. Berlin currently has 4 second-hand stores in construction.
B. Berlin has been successful in cutting its waste since 2008.
C. It is not easy to make the goal to expand the market a reality.
D. It is estimated that Berlin will be a zero-waste city by 2030.

What is the author's main purpose in writing the text？ ______

A. To introduce Berlin's new reuse shop operation.
B. To raise people's awareness of reasonable shopping.
C. To persuade people to become eco-friendly shoppers.
D. To encourage more people to donate to secondhand shops.

When was the last time you thought about breathing？ Most people usually do not. When we are healthy, breathing happens naturally and easily. Without much effect on our part, the human respiratory system（呼吸系统）works hard. Experts say we take about 20，000 breaths every day.
One such expert is James Hoyt, a doctor at the University of Colorado's Health Pulmonology Clinic. He notes our "respiratory muscles are working every minute of the day, every day of our lives." A muscle called the diaphragm（横膈膜）separates the chest and abdominal cavities（腹腔）. As we breathe in, the diaphragm tightens. The chest cavity opens, and the lungs expand. When we breathe out, the diaphragm relaxes and moves upward, pushing air out.
When you breathe deeply, the air coming in through your nose fully fills your lungs, and the lower belly（腹部）rises. On its website,Harvard Medical School notes that deep breathing may slow the heartbeat,lower blood pressure and lower stress. Deep breaths help your body fully exchange incoming oxygen with outgoing carbon dioxide. However, many people do the opposite of deep breathing. They take short breaths and have shallow breathing. Shallow breathing makes you feel short of breath and worried, or anxious.
The American Lung Association notes that shallow breathing, over time, leaves old, stale air in the lungs. This leaves less room for the diaphragm to bring in fresh oxygen. And that means lower oxygen levels and less oxygen for exercise and activity.
Several health websites explain an easy deep breathing exercise. Find a place to sit or lie down. Place one hand just below your ribs（肋骨）. Take a slow, deep breath-or inhale-through your nose. Feel your hand go up. Your stomach should rise and expand. Now breathe out slowly through your mouth. Make sure to breathe out-or exhale-all the way. Feel your hand and stomach go down.



How can we breathe air out？ ______

A. By the diaphragm's tightening.
B. By the chest cavity's opening.
C. By the lungs' expanding.
D. By the diaphragm's moving upward.

What does the author think of deep breathing？ ______

A. It's harmful.
B. It can cause anxiety.
C. It can reduce stress.
D. It's bad for the heart.

What's the probable meaning of the underlined word "stale" in paragraph 4？ ______

A. No longer new.
B. Not beneficial.
C. Poisonous.
D. Available.

Which column is the text taken from？ ______

A. Special News.
B. Health Report.
C. The Making of a Nation.
D. People in America.