1 . There are a lot of chemicals that can cause indoor air pollution. A recent project conducted has found over 900 different substances in our home are related to it. Many researchers have already examined the causes of indoor air pollution.     1    

It has been proved that different kinds of chemicals can be released by building materials and new furniture. Everything from painting and decorating products, bathroom cleaners and beauty products can contain these chemicals.     2     For instance, cooking generates a lot of harmful emissions, like frying meat in oil.

As a research from Denmark has highlighted, cooking, particularly roasting can damage our body. Roast dinners contain many potentially harmful pollutants.     3     When exposed to cooking emissions, people actually had DNA damage. It can be associated with cell repair processes that trigger cancer—causing genetic changes.     4     And what can we do with it?

As far as cooking emissions are concerned, no one is suggesting switching to takeaways.     5     For example, cooking meat at high temperatures with lots of fat produces more harmful emissions than boiling pasta. Besides, opening windows and using cooker hoods are preferable so that we can enjoy the roasted meat without those undesirable effects.

A．In the long run, these changes lead to cancer.

B．They might also arise from cooking at home.

C．A wide range of sources are under investigation.

D．Therefore, what results from indoor air pollution?

E．However, most of us have ignored their bad effects.

F．So, what are the main contributors to poor air quality?

G．But we can change how we cook to deal with the emissions.

2 . The song of the Florida grasshopper sparrow is unusual and surprisingly insect-like. But it almost fell silent forever. In 2012, Joel Sartore, the founder of National Geographic Explorer and Photo Ark received a call from the U. S. Fish and Wildlife Service: The songbird, an important ecological link in Florida’s dry grassland, was on the edge of extinction. With only a few dozen males showing up in counts, it was among North America’s most endangered bird species.

Sartore flew to Florida to photograph the bird and work with conservationists to raise awareness of the species’ difficult situation. The story appeared in outlets, such as newspapers, magazines and even the Internet, helping boost government funding for a breeding program. Thanks to these steps, there are now as many as 180 adults in the wild and researchers are working hard to bring the species back from the brink of extinction.

Like other examples of species survival, the push to save the sparrow is “a remarkable story of belief and cooperation,” says Sartore. It also shows what it takes to protect an endangered species: research, narratives, partnerships, resources and time. This journey shows the society’s mission to illustrate and protect the wonder of the world. Over the past 136 years, we’ve developed a unique Explorer-led model, combining science, exploration, education, and storytelling to drive impact. We support Explorer in more than 140 countries, including Sartore and others whose work appears in this issue: biologist André Green II, photographer Lynsey Addario and education advocate Ara Kusuma.

Sartore has been creating an “ark” of animal photos for 17 years. Portraits of more than 15, 000 species invite audiences to connect and care. With the society’s support, the images have appeared on landmarks and U. S. postage stamps, prompting on—the—ground conservation efforts such as an initiative of National Geographic Explorer and Photo Ark.

As Sartore says, “The sounds of birds are the sounds of a healthy planet. When we save a bird or another species, we’re actually saving ourselves.”

1. How does the author introduce the topic?

A．By clarifying a concept.	B．By offering an example.
C．By giving an explanation.	D．By quoting a remark.

2. Which has the similar meaning with “outlets” in paragraph 2?

A．Stores.

B．Media.

C．Exits.

D．Books

3. What contributes to the sparrow’s survival?

A．A funding program from the government.

B．An ark of animal photos in the magazine.

C．A unique initiative for species protection.

D．A joint effort from different professionals.

4. What does Sartore want to convey in the last paragraph?

A．The urgency of species’ protection.

B．The promotion of cooperative methods.

C．The importance of coexistence.

D．The situation of human survival.

3 . Relatives of starfish, brittle stars (海蛇尾) spend most of their time hiding under rocks in the ocean or digging in the sand. These shy marine creatures have no brain to speak of—just nerve cords running down each of their five wiggly arms, which join to form a nerve ring near their mouth.

“There’s no processing center. Each of the nerve cords can act independently. Instead of a boss, it’s like a committee. That seems to be enough to learn by association,” said lead author Julia Notar. This type of leaning involves associating different stimuli via a process called classical conditioning (条件反射).

Classical conditioning has been demonstrated in a handful of previous studies in starfish. But brittle stars and similarly brainless starfish have not been tested.

To find out if brittle stars have the ability of learning, the researchers put 16 black brittle stars in individual water tanks and used a video camera to record their behavior. Half the brittle stars were trained by dimming the lights for 30 minutes whenever the animals were fed. Every time the lights went out, the researchers would put a bit of shrimp in the tanks, placed just out of reach. The other half got just as much shrimp and also experienced a 30-minute dark period, but never at the same time—the animals were fed under lit conditions.

Whether it was light or dark, the animals spent most of their time hiding behind the filters in their tanks, only coming out at mealtime. But only the trained brittle stars learned to associate darkness with food. They didn’t need to smell or taste the shrimp to react.

Notar said the results are exciting because classical conditioning hasn’t really been shown definitively in this group of animals before. “Knowing that brittle stars can learn means they’re not just robotic scavengers (清道夫) cleaning up the ocean floor,” Notar said. “They’re potentially able to expect and avoid predators (捕食者) or expect food because they’re learning about their environment.”

1. What is paragraph 1 about?

A．The living habits of brittle stars.	B．The features of a brainless creature.
C．The characteristics of the starfish.	D．The definition of classical conditioning.

2. In which aspect were the two groups different in terms of experiment design?

A．The hiding time in tanks.	B．The change of feeding location.
C．The amount of the shrimp.	D．Light conditions at mealtime.

3. What does Notar’s research find?

A．Brittle stars can be trained to make a connection.

B．Brittle stars can clean up the ocean floor.

C．Brittle stars’ nerve cords can act independently.

D．Brittle stars have a sharp sense of smell.

4. What does the last paragraph indicate?

A．Brainless brittle stars can act like robots.

B．Brittle stars might keep away from catchers.

C．Brittle stars are the only ocean floor cleaners.

D．Brittle stars are adaptable to new environment.

4 . On Sunday night, the police found a baby koala in a bag in the town of Wishart in Queensland, Australia, during a traffic stop. Queensland police spokesperson Michael Beatty said that the officers asked a 50-year-old driver if she had anything to report. She then told the officers that she had a baby koala in her bag.

“Not quite believing their ears, the officers cautiously opened the bag and found this lovely boy and we’ve called him Alfred,” the spokesperson said. “The young koala is about 6 months old and weighs 1.5 kg. It appears to be healthy, though it was very thirsty.”

The police are warning people who find koalas to turn them over to authorities, rather than try to take care of them themselves. Koalas are protected in parts of Australia, including in Queensland, where they have been listed as “threatened” under the Nature Conservation Act.

Of course, koalas are also violent animals. One particularly wild koala even attacked a farmer in South Australia when she was riding along a muddy road.

“As it started running towards me, I thought I’d better speed up,” the terrified farmer told reporters. “But the road was too muddy, So I abandoned my bike and ran away. Fortunately, it ran up and attached itself to the dirty wheel — perhaps mistaking it for a eucalyptus tree.”

Deakin University biologist Desley. Whisson has some tips in case you experience this predicament. “Koalas more generally run from than to people. The farmer did the right thing by moving away from her bike,” she said. “The best advice I can give to people is to not fight with a koala displaying unusual behaviour. Make sure that there is another object between you and the koala so that it can’t climb you. Or you can just simply run. Their fingers are very sharp.”

She also believed the koala might have been confusing the sound of the bike with that of a koala mate.

1. What do the police in Wishart most likely want to tell the public?

A．Koalas are protected by law all over Australia.

B．It is illegal for the public to keep koalas in Queensland.

C．The public should stay away from violent animals.

D．Baby koalas are too violent to be kept in bags.

2. What can we learn about adult koalas?

A．They enjoy climbing bikes.	B．They have good eyesight.
C．They can be dangerous.	D．They weigh about 1.5kg.

3. What does the underlined word “predicament” in paragraph 6 mean?

A．Boring animal.	B．Interesting event.
C．Pleasant meeting.	D．Difficult situation.

4. From which is the text probably taken?

A．A research paper.	B．The Nature Conservation Act.
C．A news report.	D．An announcement from the police.

5 . Most people don’t know much about electric eels (鳗鱼), except that they produce electricity. Although not endangered, electric eels only live in one small region of the world and are hard to keep in captivity (圈养), so most people have never seen one.

The most important fact to know about electric eels is that they are not actually eels. Although it has a long body like an eel, the electric eel is actually a type of knifefish. Scientists have been confused about it for many years. The electric eel was first described by Linnaeus in 1766. At present, the electric eel is the only species in its family. It is only found in muddy, shallow waters surrounding the Amazon and Orinoco rivers in South America.

An electric eel living in water, needs to rise to the surface and breathe about once every ten minutes. In the wild, electric eels live about 15 years. In captivity by human being, they may live 22 years.

An electric eel has three organs in its belly that produce electricity. Together, the organs make up four-fifths of an eel’s body, allowing it to deliver low voltage or high voltage or use electricity for electrolocation. In other words, only 20 percent of an eel is devoted to its vital organs.

A shock from an electric eel is like the brief and sudden hit from an electric stick. Normally, the shock can’t kill a person. However, the eels can cause heart or respiratory failure from multiple shocks or in persons with underlying heart disease. More often, deaths from electric eels shocks occur when the sudden hit knocks a person in the water and they drown. Eel bodies are insulated, so they don’t normally shock themselves. However, if an eel is injured, the wound can make the eel vulnerable to electricity.

1. What can we learn about electric eels according to the passage?

A．They are close to getting extinct.	B．They are used to living in clear rivers.
C．They can breathe once every ten minutes.	D．They can possibly be raised in captivity.

2. What made scientists feel confused about electric eels?

A．The living area.	B．The origin of the name.
C．The shape of their body.	D．The reason for producing electricity.

3. What can we infer from the passage?

A．High voltage can shock an electric eel itself to death.

B．Three organs in an electric eel’s belly produce electricity.

C．Three organs in the belly can produce different voltages separately.

D．Shocks from an electric eel may be a contributing cause of a person’s death.

4. Where may be the passage taken from?

A．A website about biology.	B．A paper about endangered species.
C．A science fiction about animals.	D．An engineering course about electricity.

6 . The tickbird and the giraffe have a connection relationship that some scientists describe as win-win relationship and some as parasitism (寄生). This interspecies partnership is imbalanced in favor of the giraffe because it can live without the tickbird, while the tickbird is dependent on the giraffe for food resource.

The giraffe is a large mammal that lives in Africa along with other large grass-eaters. All these and many others host the tickbird. This bird has long been thought to remove ticks (扁虱) from its host, to the benefit of both—the bird eats the ticks, and the host is relieved of blood-sucking, disease-carrying insects—but recent studies reveal that this process is less than good. A secondary benefit to a host from the tickbirds’ presence is a sort of early warning system, since the birds make a loud sound if they sight an enemy. This is of less benefit to the giraffe than to other hosts because the giraffe has the advantage of great height and keen eyesight and is fully capable of spotting predators without the bird’s assistance. The tickbird is likely of greater benefit in this capacity to the nearsighted rhino.

They cross through the host’s hair looking for insects as their food. According to the researcher Paul Weeks, reporting in the journal Behavioral Ecology, tickbirds can and do enlarge tick bites and other wounds on their host body to seek for food resource, making the host-tickbird relationship unfair. The host, like the giraffe, however, would have a hard time keeping tickbirds off itself. So they tolerate the birds who cling to their bodies and chow down selectively at the buffet on the giraffe’s body.

1. Which statement about the tickbird is TRUE?

A．It doesn’t rely on the giraffe for food.

B．It removes ticks from its hosts.

C．It makes gentle sounds when it spots an enemy.

D．It brings more benefit to its hosts than it gets from them.

2. Why does the giraffe benefit less than other hosts according to Paragraph 2?

A．Because the giraffe has no tick on its body.

B．Because the giraffe has its own warning system.

C．Because the giraffe is tall and has sharp eyesight.

D．Because the giraffe is strong enough to protect itself.

3. The underlined phrase “cling to” can be replaced by “________”.

A．stick to

B．lead to

C．keep away

D．hold back

4. What is the suitable title for the passage?

A．Tickbird and Giraffe: Unequal Relationship	B．Tickbird and Giraffe: Friendly Relationship
C．Tickbird and Giraffe: Mysterious Relationship	D．Tickbird and Giraffe: Conflicting Relationship

7 . How has global warming changed your life? Perhaps you experience hotter summers. But for reindeer herders (驯鹿游牧民), the influence goes far beyond that.

Living in the Arctic region spreading from Russia to Sweden, local reindeer herders make a living by herding. For generations, they have been living in harmony with the cold winters with their deep understanding of snow and ice types, weather patterns and animal behaviors. This allows them to predict and prepare for winters.

However, the warming Arctic is messing up these traditional signals, making herders’ traditional ways of predicting weather less useful. In 2014, during the winter migration (迁徙) southward with their reindeer in North Russia, something unexpected happened. Heavy rainfall formed an ice shield above the lichen (地衣), normally covered by soft snow. Unable to access the lichen beneath the ice, the reindeer suffered from hunger, resulting in the deaths of tens of thousands of them.

The warming climate goes beyond threatening reindeer herders’ livelihood; it also threatens their culture. “We are an Arctic people, and our culture is written in snow. But climate change means the snow will get less and less,” Henrik Blind, a member of Sami herding family in Sweden, told The Guardian. In his language, there are over 300 words to describe snow. But with less snow, the Sami culture faces the risk of losing elements of its cultural identity.

Despite these challenges, herders have been cooperating with scientists to better deal with climate change. For example, for scientists, the difference between various types of snow is hard to tell. But local people who live with snow every day can see what scientists fail to see. At the same time, satellite data from modern scientists could help predict disasters for the local people. To combine these two different knowledge systems together, the US National Science Foundation set up the Center for Braiding Indigenous Knowledge and Science this September. The goal is to recognize the value of indigenous (土著) knowledge alongside modern research methods.

“We must realize we can’t over-consume our planet. This is urgent. We need to listen to all the indigenous people who know how to live in harmony with the planet,” Blind told The Guardian.

1. What led to the deaths of many reindeer during their winter migration southward in 2014?

A．A disease outbreak after heavy rainfall.

B．Food shortage due to ice-covered lichen.

C．Attacks by other wildlife.

D．Unexpectedly strong snowstorms.

2. How is global warming posing a risk to Arctic culture?

A．By reducing language diversity	B．By threatening their cultural elements.
C．By changing traditional eating habits.	D．By challenging ice type descriptions.

3. Why are scientists and herders cooperating?

A．To spread indigenous customs.	B．To test modern research methods.
C．To predict global natural disasters.	D．To bridge their knowledge gap.

4. What might be Blind’s attitude toward the establishment of the Center for Braiding Indigenous Knowledge and Science?

A．Supportive.

B．Opposed.

C．Worried.

D．Uninterested.

8 . Over the past 45 years, farmer Fu Benfa has planted countless trees on barren (不毛的) mountains near Qilita village in Suizhou, Hubei province. The task would have been a challenge for an able-bodied person, let alone a person with paralysis (瘫痪).

Fu, 65, was paralyzed in an accident in January 1978. News about green development through measures such as expanding forests in the province caught his attention. He got the idea that he might be able to contribute. Fu’s parents strongly disagreed because of his poor physical condition. But he insisted. His father finally acquiesced and made him a special shovel (铁锹) and straw mat (草席).

In the winter of 1978, Fu came to a barren mountain and began the task that would occupy him for decades. He sat on the straw mat and tried to dig a hole to plant a tree in, but he failed to finish it after working all day. He didn’t give up, however, and tried various kinds of movements until he became more efficient. Every day he spent more than 12 hours on the mountain. After a month, he had successfully planted 18 trees, 13 of which survived.

Three months later, he had planted more than 300 trees, most of which survived. Over the next 30 years, Fu brought green color to five mountains around his village. With the help of local governments, a forest protection volunteer service team was set up to carefully protect and guard the green mountains.

After years of study and exploration, Fu has gained rich experience and taken advantage of technology. He has taught more than 200 nearby farmers, free of charge, to increase their incomes by planting trees. Recent health problems have slowed Fu down. He has been recovering at home since February.

“Now it is difficult for me to continue planting trees in the mountains, but I will always guard this forest,” he said. “I will never change my dream.”

1. What does the underlined word “acquiesced” in Paragraph 2 mean?

A．Quit.

B．Agreed.

C．Argued.

D．Opposed.

2. What does the author intend to express in Paragraph 3?

A．Fu Benfa was far-sighted.	B．Fu Benfa suffered little.
C．Fu Benfa was physically poor.	D．Fu Benfa was strong-willed.

3. Why did Fu Benfa teach nearby farmers to plant trees?

A．To better their life.	B．To draw their interest.
C．To find more helpers.	D．To make more progress.

4. Which of the following is a suitable title for the text?

A．Planting Trees Changed the World

B．Fu Benfa Helped Farmers in the Village

C．An Able-bodied Man Amazed the Country

D．For 45 Years, a Paralyzed Man Planted Many Trees

9 . Wetlands occur wherever water meets land. Wetlands exist in every country and in every climatic zone. Healthy wetlands store carbon, regulate the water cycle, and support 40% of the world’s biodiversity.

Jiangxi Poyang Lake Nanji Wetlands

Nanji Wetlands is located in the southern part of the main lake area of Poyang Lake, covering a total area of 33,300 hectares. It is an incredibly valuable ecosystem and serves as a vital habitat for various wetland bird species, including many national first-class and second-class protected animals.

Anhui Shengjin Lake National Nature Reserve

The Anhui Shengjin Lake National Nature Reserve is a freshwater lake wetland, with an area of 33,333 hectares. It is primarily set up as the wintering grounds of rare birds. Within the reserve, there are a total of 142 bird species, including 66 species of migratory (迁徙的) birds. This reserve holds the distinction of being the largest natural wintering ground for the hooded crane (丹顶鹤) population worldwide.

Gansu Yellow River Shouqu Wetlands

The Gansu Yellow River Shouqu National Nature Reserve is located within Maqu county. It covers a total area of 203,401 hectares, with 132,067 hectares intended for wetland conservation. The primary objective of this reserve is to protect the highland wetland ecosystem, as well as the habitat of migratory birds, particularly the black-necked crane. In February 2020, it was officially approved as a Wetland of International Importance.

Guangdong Nanpeng Islands Reserve

Established in 2003, Guangdong Nanpeng Islands Reserve covers a total area of 35,679 hectares. In 2015, it was recognized and included in the International Important Wetlands Directory. The main focus of the reserve is to protect the unique underwater natural landscape, the ecosystems of the nearby coastal waters, the important rare and endangered marine (海洋的) animals.

1. Which wetland covers the largest area?

A．Nanji Wetlands.

B．Shengjin Lake National Nature Reserve.

C．Shouqu Wetlands.

D．Guangdong Nanpeng Islands Reserve.

2. What is the primary purpose of founding Shengjin Lake National Nature Reserve?

A．To preserve natural landscapes.

B．To house rare birds in winter.

C．To reproduce hooded cranes.

D．To store freshwater.

3. What does Guangdong Nanpeng Islands Reserve mainly protect?

A．Highland wetland ecosystem.	B．Marine ecosystems.
C．Underwater animals.	D．Bird habitats.

10 . 阅读短文，在空白处填入适当的内容或括号内单词的正确形式。

Over the summer break, a wave of fashionably     1     (dress) young people went to Kaifeng in Central China’s Henan province to explore the city     2     was the ancient capital of eight dynasties through a trendy “Citywalk”. They     3     (eager) shared fresh perspectives and travel encounters on various social media platforms.

“Citywalk” means the act     4     walking freely along city     5     (street) free of large and heavy bags. Such a convenient form of travel has emerged as     6     popular trend among young people in China,     7     (offer) them an avenue to experience urban culture and local traditions.

“Kaifeng is one of China’s first national historical and cultural cities, boasting a deep-seated cultural heritage. It’s an ideal destination for unhurried exploration, encouraging visitors     8     (take) a leisurely pace as they step into Kaifeng’s embrace. The heart of Kaifeng’s cultural tourism     9     (lie) in the profound culture of the Song Dynasty (960-1279). Through cultural tourism products with different themes, including architecture, cuisine     10     opera, we aim to help visitors gain a deeper appreciation of Kaifeng’s history and heritage,” said Wei, head of the city’s cultural, radio, film and tourism bureau.