3 . Pollution

Pollution happens when the environment is dirtied, by waste, chemicals, and other harmful substances(物质).Pollution is a problem all over the world. But it is especially bad in large cities with a lot of industries and cars.    1    

Wildfires, volcanoes, and industrial chemicals cause some air pollution. But most air pollution comes from burning fossil fuels (矿物燃料）These include coal, oil and natural gas. The burning of fossil fuels may release harmful gases. Air pollution may cause such diseases cancer and asthma. It also leads to polluted rain that can harm living things    2     Finally, air pollution damages the ozone layer(臭氧层)which is important because it protects Earth against harmful rays from the sun.

Causes of water pollution are easy to see. People dump(倾倒) garbage and dirty water into river, lakes and oceans. Factories or cities sometimes release poisonous chemicals, and other wastes into water. These chemicals may make the groundwater unfit to drink.    3    

Littering, or throwing garbage on the ground, is a form of land pollution. Litter can destroy the habitats of plants and animals. The buildup of dangerous chemicals in the ground is another form of land pollution. The chemicals may come from farms or factories.    4     They may even harm people who eat the polluted plants and animals.

Many governments, environmental groups, and ordinary people are working to control pollution. Governments have passed laws to keep people from releasing dangerous chemicals into the environment     5     Instead they are getting power from the sun, wind, water, and other energy sources to produce less pollution. Many communities use recycling to reduce pollution.

A．Farmers use chemical to help crops grow.

B．This type of pollution may be seen in big cities.

C．They also can harm fish and other forms of life.

D．These chemicals can spread to plants and animals.

E．In addition, air pollution may be a cause of global warming.

F．There are three main forms of pollution: air, water, and land.

G．Some companies and people are trying to use fewer fossil fuels.

4 . According to a new study from Cornell University, about one-fifth of the global population, of 2 billion people worldwide, will be forced to resettle or go deeper inland by 2100 due to the continuous rise in sea level.

The study, published in the journal Land Use Policy, showed that the growing global population could make the matter worse. The researchers expected that there are about 1.4 billon “climate change refugees(难民)” in the world by 2060 and by 2100 the number of the displaced people due to the rising sea level could reach up to two billion.

“We’re going to have more people on less land and sooner than we think,” said lead author Charles Geisler, professor at Cornell. “The future rise in global average sea level probably won’t be gradual. Yet few policy makers are observing the significant barriers that coastal climate refugees, like other refugees, will run into when they move to higher ground.”

For the study, the researchers reviewed(回顾) potential problems that climate change refugees may face if they go deeper inland. The researchers identified these land difficulties with relocation using three organizing groups. Including depletion(损耗) zones, win-lose zones and no-trespass(不得擅自进入) zones. By doing so, the researchers were able to provide primary estimates of their toll(损失) on inland resettlement space. The researchers found that some inland regions were unlikely to support new waves of climate change refugees due to the remains of war, road developments and rare natural resources.

Apart from the rising sea level, increasing storm weather and the booming global population are also having a huge influence on the number of climate change refugees. Storm can push seawater further inland. The increasing global population requires more land even as the ocean swallows up rich costal zones and river deltas(三角洲). These force people to search for new places to move to higher ground.

1. What would happen if the sea level were to rise?

A．2 billion people would be “refugees” by 2060.

B．50% of the population would lose their homes.

C．Inland regions would become more crowded.

D．Coastal regions would be polluted seriously.

2. What can be inferred from Charles Geisler’s words?

A．The sea level will go up in a little-by-little way.

B．Moving to higher land isn’t the key solution.

C．Land and population vary according to climate change.

D．Policy makers should think more for climate change refugees.

3. Why do climate change refugees fail to move to some inland regions?

A．Because they can’t live a common life there.

B．Because they can’t adapt to the climate there.

C．Because they may consume more than expected.

D．Because they will destroy the natural resources.

4. What does the author stress in the last paragraph?

A．Global warming is a double-edged sword.

B．In the future climate will become worse.

C．The earth will see more climate change refugees.

D．Sea will bring humans more disadvantages.

5 . A robot created by Washington State University (WSU) scientists could help elderly people with dementia (痴呆) and other limitations live independently in their own homes.

The Robot Activity Support System, or RAS, uses sensors installed in a WSU smart home to determine where its residents are, what they are doing and when they need assistance with daily activities. It navigates (定位) through rooms and around obstacles to find people on its own, provides video instructions on how to do simple tasks and can even lead its owner to objects like their medication or a snack in the kitchen.

“RAS combines the convenience of a mobile robot with the activity detection technology of a WSU smart home to provide assistance in the moment, as the need for help is detected,” said Bryan Minor, a postdoctoral researcher in the WSU School of Electrical Engineering and Computer Science.

Currently, an estimated 50 percent of adults over the age of 85 need assistance with every day activities such as preparing meals and taking medication and the annual cost for this assistance in the US is nearly $2 trillion. With the number of adults over 85 expected to triple by 2050, researchers hope that technologies like RAS and the WSU smart home will relieve some of the financial strain on the healthcare system by making it easier for older adults to live alone.

RAS is the first robot researchers have tried to incorporate into their smart home environment. They recently published a study in the journal Cognitive Systems Research that demonstrates how RAS could make life easier for older adults struggling to live independently.

“While we are still in an early stage of development, our initial results with RAS have been promising,” Minor said. “The next step in the research will be to test RAS’ performance with a group of older adults to get a better idea of what prompts, video reminders and other preferences they have regarding the robot.”

1. How does RAS serve elderly people?

A．Through sensors.	B．Through objects.
C．Through a mobile robot.	D．Through their daily activities.

2. What can we know about RAS?

A．It is the first robot used in daily life.	B．Its function remains to be tested.
C．It can locate people and do any task.	D．It can cook for owners on its own.

3. What’s Minor’s attitude toward the future of RAS?

A．Doubtful.	B．Negative.
C．Optimistic.	D．Uncertain.

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

A．Elderly people leave the nursing home.

B．Smart Home Tests first elder-Care robot.

C．RAS, the first robot to make home smart.

D．Older adults have benefited from RAS.

6 . Google previously announced successful tests of machine learning systems designed to assist doctors. In one case, Google reported AI had examined eye diseases with equal accuracy to doctors. Other tests showed that machine learning can be used to study large amounts of patient data to predict future medical events.

Now the company has published two new studies showing a high level of success in identifying metastatic breast cancer. Metastatic means that cancer has spread from its main area to other parts of the body. Metastatic breast cancer is one of the deadliest, causing about 90 percent of all breast cancer deaths worldwide.

In metastatic breast cancer patients, the cancer often travels to nearby lymph nodes(淋巴结). Usually doctors examine lymph node tissue under a microscope to see whether cancer is present. Google notes that previous studies have shown that up to one-fourth of metastatic lymph node classifications end up being changed after a second examination. In addition, studies show that small metastatic material can be missed up to 67 percent of the time when examinations happen under extreme time restrictions.

Google says it created a mathematical algorithm(算法). The algorithm, called Lymph Node Assistant, is trained to find characteristics of tissue affected by metastatic cancer. When the system examined tissue images(图像), it was able to differentiate between metastatic cancer and non-cancer 99 percent of the time. In addition, the Lymph Node Assistant is highly effective at finding the positions of the cancers. Some of these positions would be too small for doctors themselves to identify. The research also showed that the algorithm method can reduce the usual time needed to examine the disease by about 50 percent.

But Google makes clear the AI-based system is not meant to replace the work of medical professionals. Instead, it is designed to reduce the number of false identifications and help doctors work faster and more effectively.

1. What is the main idea of Paragraph 1?

A．Google became a pioneer in training doctors.

B．Machine learning is able to stop future medical events.

C．Google developed artificial intelligence to help doctors.

D．Artificial intelligence cured eye diseases with equal accuracy to doctors.

2. What can we infer about metastatic breast cancer?

A．One-fourth of the metastatic breast cancer patients die in the end.

B．Metastatic breast cancer is very difficult to identify.

C．It results in 90 percent of deaths of all cancers.

D．It can be identified after a second examination.

3. What is the advantage of Google’s new mathematical algorithm?

A．It can offer effective treatment.

B．It can tell the exact positions of cancers

C．It costs 99 percent less time than before.

D．It improves the accuracy of identifying cancers by 50%.

4. What influence will the mathematical algorithm bring?

A．False identification of cancers will be avoided.

B．More effective prevention of cancers will be found.

C．The number of medical professionals will be reduced.

D．Doctors can have a faster understanding of patients’ condition.

7 . One day, “supercharged plants” may help feed people around the world. Supercharged plants are ones that grow faster than normal plant life. Scientists can speed up the growth by modifying, or changing, the structure of plants' genes. The modifications make them react quickly to changes in light. This all has to do with photosynthesis(光合作用), the process in which plants turn sunlight, carbon dioxide and water into food.

Plants grow fastest in the sun. That is when they make the most food for themselves. But their rate of growth can slow when things like clouds or trees block sunlight. But when the sun returns, it can take many minutes for growth to speed up again.

This can be a problem because it means some of our most important crop plants are not as productive as they could be. Researchers say demand for food is expected to increase up to 70 percent by the middle of the century. They also note rising temperatures on Earth's surface. That is why they are looking for ways to improve photosynthesis and make plants more productive.

Steve Long is a plant biologist at the University of Illinois. He wanted to find a way to help plants get back up to speed quickly after a period of darkness. So he and his team added genes that shortened the recovery time. It also increased the speed at which the plants grew. His modified plants grew up to 20 percent more than untreated ones.

In Long's study, his group used a form of genetic engineering called transgenics (转基因). It means taking genes from one plant, then putting them into another. Now they are experimenting soybeans, rice, cowpeas and cassavas.

1. What is the advantage of supercharged plants?

A．They can grow more quickly.

B．They can grow in severe conditions.

C．They can offer high-quality grains.

D．They can replace normal plants.

2. What can make plant growth slow down?

A．Too hot weather.	B．Old farming methods.
C．Lack of sunlight.	D．Too much sunlight.

3. What was Steve Long's goal in his study?

A．To find out what makes plants grow slowly.

B．To create a new plant that can grow with weak sunlight.

C．To find another way to help plants benefit each other.

D．To make plants recover quickly when the sun returns.

4. How can researchers shorten the recovery time of plants?

A．By changing their nature.	B．By adding new genes to them.
C．By developing new plants.	D．By supplying more sunlight.

8 . Located at Europe’s biggest water park, the Galaxy Erding in South Germany, the world’s first VR water slide takes the exciting experience to a whole new level by offering thrill-seekers the choice of three attractive worlds --- Space, Sky, or Snow. By simply wearing a headset, riders can slide through a magical alien world, follow beautiful butterflies around floating islands or put themselves in a white winter wonderland. To make the experience even more heart-stopping, the 160-meter-long ride that lasts about 35 seconds has two uphill tracks that provide a roller-coaster-like experience.

While the tire slide, which has been successfully tested by almost 10,000 park goers since it opened in February 2018, is impressive, the technology behind it, developed by California startup Ballast is even more so. The specially-created waterproof headsets can be worn in water up to a few meters deep, without harming the delicate Samsung Galaxy S8 mobile devices that run the custom software for the VR experiences. The headsets also charge wirelessly (无线地), allowing park operators to swap out sets throughout the day.

The biggest challenge the company faced, however, was providing a suitable VR experience for everyone. That’s because unlike roller coasters, where the speed is fixed for all riders, water slide speeds vary depending on the weight of the person. To overcome the issue, Ballast fixed   smart sensors (传感器) in important areas along the slide to keep track of the rider’s progress at   all times. The information, conveyed through the headset, allows the custom software to adjust his or her location within the virtual world accordingly, making for a smooth, seasickness free ride for all.

Though Ballast is thrilled at Space Glider’s success, the company has bigger ambitions. They want to create an experience where guests will be able to swim underwater surrounded by virtual dolphins, whales, and even sharks, without wearing the heavy headsets!

1. What can people do if they go to the Galaxy Erding?

A．They can swim with dolphins.

B．They can explore the outer space.

C．They can experience VR water slide.

D．They can swap out sets all day long.

2. Which statement is NOT true according to the passage?

A．The tire slide has been successfully tested so far.

B．Water slide speed vary depending on the age of the person.

C．Thrill-seekers take the exciting experience by wearing a headset.

D．The specially-created waterproof headsets can be applied in water.

3. What can help park goers experience a smooth, seasickness free ride?

A．The painkillers.

B．The fixed speed.

C．A sensor fixed in important areas.

D．Virtual dolphins, whales and sharks.

4. What is the author’s attitude towards the VR water slide?

A．objective

B．subjective

C．opposed

D．indifferent

9 . Modern lifestyles are generally quite different from those of our hunter-gatherer ancestors, a fact that some claim as the cause of the current rise in global obesity, but new results published July 25 in the open access journal PLOS ONE find that there is no difference between the energy expenditure(耗费) of modern hunter-gatherers and Westerners, casting doubt on this theory.

The research team behind the study, led by Herman Pontzer of Hunter College in New York City, along with David Raichlen of the University of Arizona and Brian M. Wood of Stanford measured daily energy expenditure among the Hadza, a population of traditional hunter-gatherers living in the open Savannah of northern Tanzania. Despite spending their days hiking long distances to seek for wild plants and game, the Hadza burned no more calories each day than adults in the U.S. and Europe. The team ran several analyses accounting for the effects of body weight, body fat percentage, age, and gender. In all analyses, daily energy expenditure among the Hadza hunter-gatherers was indistinguishable(难以区分的) from that of Westerners. The study was the first to measure energy expenditure in hunter-gatherers directly; previous studies had relied entirely on estimates.

These findings overturn the long-held assumption that our hunter-gatherer ancestors expended more energy than modern populations, and challenge the view that obesity in Western populations results from decreased energy expenditure. Instead, the similarity in daily energy expenditure across a broad range of lifestyles suggests that habitual metabolic(新陈代谢的) rates are relatively constant among human populations. This in turn supports the view that the current rise in obesity is due to increased food consumption, not decreased energy expenditure. It means we have more to learn about human physiology(生理学) and health, particularly in non-Western settings.

"These results highlight the complexity of energy expenditure. It's not simply a function of physical activity," says Pontzer.” Our metabolic rates may be more a reflection of our shared evolutionary past than our diverse modern lifestyles."

1. According to the new research, hunter-gatherers consume _________.

A．the same energy as Westerners	B．more energy than Westerners
C．less energy than Westerners	D．the same food as Westerners

2. How did the research team do the new research?

A．By comparing hiking distances.	B．By identifying wild plants and game.
C．By estimating daily energy expenditure.	D．By measuring daily energy expenditure.

3. People have long assumed that _________.

A．the rise in obesity is due to increased food consumption

B．decreased energy expenditure makes Westerners fat

C．daily energy expenditure stays the same in history

D．humans’ habitual metabolic rates are unchanged

4. Which of the following can reflect our shared evolutionary past?

A．Our physiology activity.	B．Our energy expenditure.
C．Our metabolic rates.	D．Our modern lifestyle.

10 . Antarctica(南极洲)’s melting ice, which has caused global sea levels to rise by at least 13.8 millimeters over the past 40 years, was thought to primarily come from the unstable West Antarctic Ice Sheet(WAIS). Now, scientists have found that the East Antarctic Ice Sheet (EAIS)—considered largely unaffected by climate change—may also be melting at an unexpectedly rapid speed.

The WAIS, whose base is below sea level, has long been considered the most likely to break down. Besides gravity, a deep current of warm water slips beneath the sheet, melting it from below until it becomes a floating shelf at risk of breaking away. In contrast, extreme cold and a base mostly above sea level are thought to keep the EAIS relatively safe from warm waters.

But as greenhouse gases warm much of the planet, driving stronger polar winds, some scientists think warm water carried by a circular current will start to invade East Antarctica’s once unassailable ice. A cooperation of more than 60 scientists last year, published in Nature, estimated that the EAIS actually added about 5 billion tons of ice each year from 1992 to 2017.

Eric Rignot of the University of California, Irvine, and colleagues combined 40 years of satellite imagery and climate modeling and found that overall Antarctica now sends six times more ice into the sea each year than it did in 1979, with the majority coming from West Antarctica. But East Antarctica was responsible for more than 30% of Antarctica’s contribution to the 13.8-millimeter sea level rise over the past 40 years. “The more we look at this system the more we realize this is fragile,” Rignot says. “Once these glaciers become unstable there is no red button to press to stop it.”

Rignot hopes the study brings greater attention to a part of Antarctica that has traditionally been understudied. Helen Fricker, a glaciologist (冰川学家) in California, agrees. “We need to monitor the entire Antarctica and we just can’t do that without international cooperation.”

1. What is the new finding of scientists?

A．The east Antarctica is losing ice at an increasing rate.

B．The west Antarctica is melting six times faster than in 1979.

C．5 billion tons of ice is added to Antarctica each year.

D．The sea level has risen by 13.8 mm over the past 40 years.

2. Which factor leads to the EAIS’s melting fast?

A．A base mostly over sea level.	B．The force of gravity.
C．The invasion of a warm current.	D．Extremely low temperature.

3. Which of the following best explains “unassailable” underlined in Para. 3 ?

A．Fragile.	B．Unattackable.
C．Mild.	D．Unstable.

4. Which way does Helen Fricker specially advocate?

A．Satellite imagery.	B．Global monitoring.
C．Worldwide climate modeling.	D．Worldwide combined efforts.