3 . On paper, hydrogen（H2）looks like a dream fuel. Coal, oil, and natural gas produce carbon dioxide, which warms the earth when burned, Hydrogen produces pure water. Hydrogen packs more energy into less space than a battery（but certainly less than petrol）. Also, empty tanks（燃料箱）can be refilled with hydrogen much faster than refilling empty batteries with electricity.

While in practice, things are trickier. Storing a meaningful amount of hydrogen gas requires pressing it several hundred-fold. Changing it into the liquid form is another option, but it should be cooled to-253C. Both processes require a heavy and strong tank. While a 700 bar tank is acceptable for a city bus or a truck, adapting it for use in small vehicles is very difficult because the pressure during refilling would be too great.

The solution? Powerpaste.

A German team of researchers, led by Marcus Vogt, have come up with an interesting "powerpaste", which can store hydrogen energy at atmospheric pressure, ready for release when needed. It is so named because it comes in tubes and looks like toothpaste（牙膏）, not in its traditional form of gas.

The main ingredient（原料）of the paste is magnesium hydride, a substance that reacts with water to form hydrogen. The escaped hydrogen can then be directed into a fuel cell, where it reacts with oxygen from the air to produce electric power.

Refueling is very simple, as instead of going to a filling station, drivers and riders can simply replace an empty tube with a new one and refill the water tank.

Given that powerpaste only begins to break down at temperatures of around 250℃ it remains safe even when a vehicle stands in the baking sun for hours.

However, we will have to be patient. Just because researchers have succeeded in developing a new fueling way does not mean that we can expect to see such vehicles on the road anytime soon. It will indeed be several years before this concept is turned into reality.

1. As a fuel, what is the advantage of hydrogen over oil?

A．Refilling empty tanks will be more convenient.

B．It is less likely to worsen global warming

C．More energy can be packed in the same space.

D．It will produce pure water for people to drink.

2. What is Paragraph 2 mainly about?

A．The practical difficulties to use hydrogen as fuel in small vehicles.

B．The detailed processes of adapting a strong tank in small vehicles.

C．The differences in fueling between large vehicles and small ones.

D．The tricks of building strong tanks in small vehicles.

3. The author mentions the refueling process to show that powerpaste is______________.

A．inexpensive

B．powerful

C．convenient

D．environment-friendly

4. Why does the author call on the readers to be patient?

A．Powerpaste-driven vehicles sometimes move very slowly on the road.

B．Practical use of powerpaste-driven vehicles will not come very soon.

C．Powerpaste-driven vehicles can only work after being in the sun for hours

D．It will be years before the researchers work out the concept of powerpaste.

4 . Christmas is on the way: 4 gift ideas from Stanford's bookshop.

Shipping Areas Tea Towel, £9. 99 (enjoying a 10% discount)

We are a nation of sailors who rely on weather forecasts to keep safe. This book will help you understand the shipping forecast, with the 30 shipping areas mentioned in the National Weather Service. So, the next time you turn on the radio and hear about high winds in Cromarty, Forth and Tyne, you'll know that they mean strong winds in these areas. You'll be wiser to make some preparations.

The Writer's Map, £30 (enjoying a 5% discount)

The Writer's Map combines maps and literature. Many writers use maps to plan out their stories. This book collects maps that appear in fiction and non-fiction. JRR Tolkien, a fantasy novel writer, said, “The fact that many books choose to contain one map is evidence to the importance of maps. I wisely started with a map, and made the story fit.”

Brutalist London Map, £8 (enjoying a 5% discount)

You either love it or you hate it. Said to have been coined (创造) in the late 1950s from the French raw concrete, brutalism (野兽派艺术) was a big influence on the 1960s London’s finest examples of brutalism. Brutalism maps of other cities, including Paris, Washington and Sydney, are also available.

The Ordnance Survey Puzzle Book, £14. 99 (enjoying a 10% & discount)

The national mapping agency, Ordnance Survey, has been mapping the Great Britain for many years. The Ordnance Survey Puzzle Book includes word puzzles and various mathematical challenges. It includes maps containing rare geographical characteristics or places of special cultural interest. It will make you look more closely at every map and test your map-reading knowledge.

1. Shipping Areas Tea Towel can help sailors ________.

A．know world-famous shipping areas

B．prepare for bad weather in advance

C．have the ability to predict weather

D．judge the quality of various ships

2. What do Brutalist London Map and The Ordnance Survey Puzzle Book have in common?

A．They are both brought out by the same publisher.

B．They both aim to test readers' map-reading skill.

C．They can both reflect the history of Britain.

D．They both include challenging puzzles.

3. What's the writer's purpose of writing the text?

A．To advertise four books.

B．To compare four books.

C．To appeal to people to read.

D．To show different maps.

5 . 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.

1. 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

2. 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.

3. 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.

4. What's the author's attitude to the new repellents?

A．Disapproving

B．Negative

C．Objective

D．Subjective

6 . A 15-year-old scientist and inventor has been named as Time's first ever Kid of the Year.

Rao is a high school student from Colorado. She was chosen from 5,000 U.S.-based nominees ( 提 名 ). Time said in a statement that Rao stood out for her ability to apply scientific ideas to real-world problems and her efforts to motivate other kids to take up their own causes. Rao told the Associated Press that the prize is “nothing that I could have ever imagined. And I'm so grateful and just so excited that we're really taking a look at the upcoming generation and our generation, since the future is in our hands.” She insists that starting out small doesn't matter, as long as you're enthusiastic about it.

It's just the latest recognition for the teenager, who was named last year to the Forbes 30 Under 30 list. Rao won praise in 2017 after she developed a portable device（设备） to detect lead (铅) in water. She went on to cooperate with scientists in the water industry to try to get the device on the market.

The young scientist has also developed an app called Kindly that uses artificial intelligence to help prevent cyberbullying (网络欺凌). It allows teens to type in a word or phrase to find out if the words they're using are hurtful and amount to（等于）bullying, and thus should be avoided.

In an interview with Time, Rao said that her pursuits（追求） in science started early as a way to improve conditions in society. In a world where science is increasingly questioned or challenged, Rao insists that its pursuit is an important act of kindness. It is the best way that a younger generation can better the world. Science and technology are being employed as never before to handle various issues, such as global warming, the outbreak of disease and so on, she noted.

“We have science in everything we're involved in, and I think that's the biggest thing to put out there, that science is cool, invention is cool, and anybody can be an inventor," Rao said.“ Anybody can do science.

1. What is one of the reasons for Rao being honored by Time?

A．The up-to-date ideas she had come up with.

B．The large amounts of time she had devoted.

C．The influence she has on young generations.

D．The optimistic attitude she holds to the future.

2. Rao's inventions mentioned in the passage can be described as _______.

A．functional	B．environment-friendly
C．efficient	D．money-saving

3. What contributes to Rao's enthusiasm for science?

A．Her tolerance for problems.	B．Her amazing brain power.
C．Her exposure to challenges.	D．Her concern about society.

4. What can be a suitable title for the passage?

A．High School Student Struggling for Big Dream

B．Young Scientist Named TIME's Kid of the Year

C．Scientific Achievements Applied to Our Real Life

D．Advanced Inventions Used in Bettering the World

7 . Non-Credit Courses

The Pre-College Program offers non-credit courses. Students will experience college-level courses given by some of our college’s leading experts and will receive written feedback (反馈) on their work at the end of the course. Pre-College students will also receive a grade of Satisfactory/Unsatisfactory and a certificate of completion at the conclusion of the program.

All non-credit courses meet from 9:00 a. m.-11:30 a. m. daily and may have additional requirements in the afternoons or evenings.

COURSE: Case Studies in Neuroscience

·June 11— July 2

·Leah Roesch

Using student-centered, active-learning methods and real-world examples, this course is designed to provide a fuller understanding of how the human brain works.

COURSE: Psychology of Creativity

·June 15—June 28

·Marshall Duke

Why are certain people so creative? Is it genetic (遗传的), or a result of childhood experience? Are they different from everyone else? This popular psychology course highlights the different theories of creativity.

COURSE: Creative Storytelling

·June 21 — July 3

·Edith Freni

This college-level course in creative storytelling functions as an introduction to a variety of storytelling techniques that appear in different forms of creative writing, such as short fiction and playwriting.

COURSE: Sports Economics

·July 19 — August 1

·Christina DePasquale

In this course we will analyze many interesting aspects of the sports industry: sports leagues, ticket pricing, salary negotiations, discrimination, and NCAA policies to name a few.

1. Who is the text intended for?

A．The general public.	B．College freshmen.
C．Educational experts.	D．High school students.

2. Which course can you take if you are free only in June?

A．Sports Economics.	B．Creative Storytelling.
C．Psychology of Creativity.	D．Case Studies in Neuroscience.

3. Whose course should you choose if you are interested in creative writing?

A．Leah Roesch’s.	B．Edith Freni’s.
C．Marshall Duke’s.	D．Christina DePasquale’s.

8 . Nowadays technologies benefit us a lot in our daily life, but if not properly used, they can affect our health．The bed is supposed to be reserved as a place for sleep, but people tend to read an iPad a lot in bed before they go to sleep．

Charles Czeisler, a professor at Harvard Medical School, and his colleagues got a small group of people for an experiment．For five days in a row, the people read either a paper book or an iPad for four hours before sleep．Their sleep patterns were monitored all night．Before and after each trial period, the people took hourly blood tests to paint a day-long picture of just how much melatonin（褪黑激素） was in their blood at any given time．

When subjects read on the iPad as compared to the paper books, they reported feeling less sleepy at night and less active the following morning．People also took longer to fall asleep on the iPad nights, and the blood tests showed that their melatonin secretion（分泌） was delayed by an hour and a half．

The researchers conclude in today's journal article that given the rise of e-readers and the increasingly widespread use of e-things among children and adolescents, more research into the long-term consequences of these devices on health and safety is urgently needed．Czeisler and colleagues go on, in the research paper, to note "Reading an iPad in bed may increase cancer risk"．

However, software has been developed that can reduce some of the blue light from the screens of phones and computers according to time of day, and there are also glasses that are made to filter（过滤） short wavelengths．While they seem like a logical solution for the nighttime tech users, it needs more research．

1. In Charles Czeisler's experiment, what were all the subjects asked to do?

A．Sit in a row and receive the strict tests．

B．Have their sleep patterns observed all night．

C．Read a paper book and an iPad at the same time．

D．Have their blood tested per hour during the trial．

2. What were the iPad readers likely to do according to the third paragraph?

A．They felt less sleepy and tired in the day．

B．They fell asleep more easily after reading．

C．They became less energetic the next morning．

D．They had a lot more melatonin secretions．

3. What can the special software recently developed do for e-readers?

A．It can remove the blue light from your devices completely．

B．It can help prevent eyes being harmed by short wavelengths．

C．It can weaken the harm done by doing nighttime e-reading．

D．It can be used in all the e-things widely and safely．

4. Which of the following can be the best title for the text?

A．Wrong behaviors before bedtime．	B．New software for night e-readers．
C．No games on the iPad in bed．	D．No e-reading in bed before sleep．

9 . Social distancing is not a new concept in the natural world, where infectious diseases are commonplace. Through specialized senses animals can detect certain diseases and change their behavior to avoid getting ill.

In 1966, while studying chimps (猩猩) in a Tanzanian national park, zoologist Jane Goodall observed a chimp named McGregor who had caught a highly infectious virus. His fellow chimps attacked him and threw him out of the troop. In one instance, McGregor approached chimps in a tree. He reached out a hand in greeting, but the others moved away without a backward glance.

“For a full two minutes, old McGregor sat motionless, staring after them,” Goodall notes in her 1971 book In the Shadow of Man. “It’s really not that different to how some societies react today to such a tragedy.”

Not all animals are so aggressive toward their ailing neighbors. Sometimes it’s as simple as avoiding those who may infect you.

When Kiesecker, a lead scientist in America, studied American bullfrog in the late 1990s, he found that bullfrogs could not only detect a deadly smell of infection in other bullfrogs, but healthy members actively avoided those that were sick. Bullfrogs rely on chemicals signals to determine who is sick or not.

Caribbean lobsters also shun diseased members of their community, well before they become infectious. It takes about eight weeks for lobsters infected with the deadly virus Panulirus argus mininuceovirus to become dangerous to others. Normally social animals, lobsters begin keeping away from the diseased as early as four weeks after infection – once the lobsters can smell certain chemicals released by sick individuals.

Overall, it’s important to note that, unlike us, animals don’t realize if they stay home, they might actually reduce the infection rate,” Kiesecker explains. “As humans, we have that ability. It’s a big difference.”

1. What can we learn about the chimps from Goodall’s observation?

A．They kept a distance from one another.

B．They became aggressive when infected.

C．The infected avoided contact with others.

D．The infected were forced to leave the group.

2. What does the underlined word “shun” in Paragraph 6 probably mean?

A．Avoid.

B．Cure.

C．Get rid of.

D．Get along with.

3. How are humans different from animals according to Kiesecker?

A．Humans are more sensitive to virus.

B．Humans are less likely to get infected.

C．Humans treat infectious diseases in a wiser way.

D．Humans can detect chemical signals more quickly.

4. Which might be the best title for the text?

A．Help Me Out

B．Leave Me Alone

C．Stay Away From Us

D．Stay Home Stay Healthy

10 . Claire Wyatt, a 24-year-old British volunteer, led eight Cambodians living with disabilities on a 155-mile bike ride from Phnom Penh, the nation’s capital, to Siem Reap to raise money and deliver supplies to those in need in the coronavirus pandemic(新冠病毒大流行).

“Leading this trip was an incredibly special experience for me,” said Claire. “Not only was I encouraged by the determination of each and every rider, but also the team taught me every day not to focus on their disability.”

When she was first asked to lead the trip, Claire admitted, she was feeling nervous about her team traveling such a distance in just a few days because cycling with a disability can come with added physical and emotional challenges.

One team member named Dy, who lost an arm in an accident, biked using just one arm to balance. Another named Vulta could only pedal on one side due to polio(小儿麻痹). Despite all the difficulties, Claire realized quickly that she didn’t have to worry about her team. She saw them deal with rough area that she had seen abled cyclists give up on before.

The volunteers covered the distance in just four days, not only helping so many people across the country, but also overcoming huge difficulties to get there.

“The best thing about this ride is that the riders have all volunteered their time to do this. They are so enthusiastic about Cambodia and raising money for others in need,” said Claire. “The money raised will feed 99 families in Siem Reap.”

Claire recalled her favorite moment of the experience, when one of the cyclists pushed an exhausted teammate up a hill for 2 miles. “One moment that stood out for me was when Naret, our only female rider, was feeling tired,” she said. “Her fellow rider gently put his hand on her back and pushed her for 2 miles! They were encouraging each other to push through the tiredness.”

1. Why did Claire and eight Cambodians cycle 155 miles?

A．To challenge themselves.	B．To help out needy people.
C．To take part in a competition.	D．To raise money for the disabled.

2. What worried Claire before the ride?

A．She might be injured on the road.	B．She would be unable to lead the team.
C．Her team might be looked down on.	D．Her team couldn’t finish the route.

3. Which of the following can best describe the team?

A．Confident, calm and friendly.	B．Honest, patient and open-minded.
C．Strong-minded, brave and caring.	D．Curious, creative and experienced.

4. What did Claire think of the journey?

A．It could have taken less time.

B．It was amazing and inspiring.

C．It changed her idea about human nature.

D．It was more difficult than she had expected.