1 . A lot of health care are connected with being around trees.     1     According to one 2015 study, a walk in the woods can make you feel seven years younger.

They also do a great deal of good for the environment by reducing air pollution and taking in carbon dioxide from the atmosphere.     2     A new study by researchers at University College London found that the trees in the London Borough (自治市) of Camden store as much carbon per hectare (公顷) as rainforests.

A tree’s ability to take in carbon dioxide is especially useful when the tree.is in cities or towns, where there are too many industrial activities. For the study, the researchers used laser scanning methods to take their own carbon readings of trees from the ground as well as the air.     3     They were able to know there are about 85,000 trees in Camden, where the university is based.

They determined that Camden had a median carton density (浓度) of around 55 tons of carbon per hectare (t/ha). Greener areas of the borough, like Highgate Cemetery, had a carbon density of 380 t/ha — levels that are typically seen in rainforests.     4    

So what exactly does this mean? Trees could help cool the atmosphere by removing carbon dioxide from the air. However, some climate scientists argue that it’s more complicated (复杂的) than that.     5     Still, with all of the other benefits trees offer, planting a seed or two couldn’t hurt.

A．We need to protect the ones we already have.

B．Global warming is happening at a faster rate than ever.

C．These benefits aren’t just felt in the countryside, either.

D．For comparison, major cities in the US have a carbon density of 7.7.

E．They have been known to reduce people’s stress and improve overall mental health.

F．Then they compared their findings with the data from the UK Environment Agency.

G．They think the impact of tree-planting activities today may not be seen for many years.

2 . 阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

Plant lovers believe that talking to plants helps them grow. Scientists have discovered there could be real     1     (true) in this belief. Researchers have discovered that plants give off sounds when they are stressed. The sounds are quite similar     2     a human cry. Unfortunately, plant sounds are at too high a frequency for the human ear     3     (pick) up. Humans can only hear frequencies of up to 16 kilohertz (赫兹). Using special Al technology, scientists can now pick up sounds     4     (send) out by plants that are up to 250 kilohertz. The Al can also tell differences between different types of plant sounds.

The research     5     (do) in a greenhouse at Israel’s Tel Aviy University. Lead researcher Professor Lilach Hadany said: “Plants usually give off sounds when they     6     (be) under stress. Each plant and each type of stress is connected with     7     specific sound.” She suggested that crop fields could be quite     8     (noise), saying “While unable to be picked up by the human ear, the sounds given off by plants can be heard by bats,     9     (mouse) and insects. Understanding these sounds could help us know when crops need watering,     10     means farmers could water their crops more efficiently and thus save water and money.

3 . A solar tree is a structure like a tree that generates solar energy using photovoltaic panels (太阳能光伏板). It helps solve an urgent global challenge: Replacing greenhouse gas-emitting energy sources like oil and gas with renewable energy. But the power generation potential of solar trees is relatively limited, and their primary purpose is to raise public awareness about renewable energy by getting people to notice and interact with solar energy in new ways.

Solar trees generally have a firm metal, plastic, or stone base that extends up and out into “branches” on which solar panels are mounted. Beyond this basic structure, there is great diversity in the design of solar tree units. The solar tree’s photovoltaic “leaves” absorb sunlight, converting it into electricity that is conducted down through the trunk-like central pillar of the structure to an inside battery. Many designs feature rotating (旋转的) panels that can move throughout the day in order to obtain the greatest amount of sunlight.

Solar trees help power homes, businesses, and public services. They can create shade to help reduce the urban heat island effect and provide shelter in severe weather such as rainstorms and heatwaves, creating greater urban adapting ability in the face of climate change. They also enhance public spaces, providing charging stations, and powering streetlights.

In comparison to other kinds of ground-mounted solar panel devices, solar trees don’t require much land. They make solar energy generation possible in areas with little land that can’t support vast solar arrays, as well as places that lack sufficient rooftop space for panels. However, solar panels are much cheaper than solar trees at present and have far greater energy generation capacity. Therefore, present solar tree designs often serve as a extra source rather than as a primary energy source.

At present, solar trees aren’t designed as large-scale solar projects, which limits their ability to contribute to the low-carbon energy transition. Still, their varied designs are appealing. This makes solar trees effective at displaying and thereby educating people about solar energy, and promoting a business or organization’s commitment to renewable energy.

1. What is the main purpose of building solar trees?

A．To beautify the urban environment.	B．To draw public attention to solar energy.
C．To replace non-renewable energy resources.	D．To provide charging services in emergencies.

2. What do we know about a solar tree?

A．It stores energy in its own battery.

B．It can adjust its height automatically.

C．It is made of environmentally friendly materials.

D．It transforms sunlight into electricity by its metal base.

3. What does the third paragraph mainly talk about?

A．The design features of solar trees.	B．The ways of saving energy in cities.
C．The benefits of solar trees to humans.	D．The difficulties of promoting solar trees.

4. What is the advantage of solar trees over other ground-mounted solar panel devices?

A．They occupy much less land.	B．They are cheaper to manufacture.
C．They are more effective in generating energy.	D．They can work in various weather conditions.

4 . 阅读下面材料，在空白处填入适当的内容(1个单词)或括号内单词的正确形式。

Food from the air

Everyone has seen plants growing, but have you ever thought     1     they get their food? In the seventeenth century, a European scientist     2     (call) Van Helmot asked this question. Like most people, he thought that plants must get their food from soil. However, Van Helmot decided       3     (test) the theory with experiments.

First, he dried some soil, put it into a pot and weighed it. Next, he weighed a small tree, planted it in the pot and added rain water. Then, he watered it     4     (regular) with rain water.

After five years, he removed the tree from the pot and weighed it again. He found that the tree had gained     5     huge amount of weight. When he weighed the soil, however, it was almost exactly the same as it had been five years    6    . So Van Helmot drew the    7    (conclude) that the tree grew by drinking water. Though it turned out to be wrong, he showed the importance of the use of scientific evidence to support ideas.

We now know that plants and trees make their own food. Their leaves, when exposed     8     the air and sun, are like factories    9     can change the energy from the sun into chemical energy. During this process (过程), oxygen and sugar     10     (produce). The oxygen is released back into the air, and the sugar is used by the plant as food.

5 . Why did the woman’s plants die, according to the man?

A．From not enough water.

B．From not enough sun.

C．From not enough plant food.

6 . 阅读下面短文, 在空白处填入1个适当的单词或括号内单词的正确形式。

Camellias (山茶花) are available in a great range     1     colors — red, pink, white and mixed colors. For the longest time, the golden camellias lived in a valley     2     was unknown to the outside world.

In the 1960s, Chinese scientists announced their discovery of the golden camellias. It was an     3     (amaze) announcement for the international gardening community. Also, the discovery made     4     achievable to create yellow camellias, though creating a new kind of golden camellia was not very easy.

Unfortunately, in the past, golden camellias were cut down in large numbers because     5     (local) needed the limited land space for farming. In 1986, a nature reserve (自然保护区)     6     (build) in a mountain valley from 200 to 500 meters above sea level, so the camellias could be well protected. Years ago, Huang Zainian and his brothers took up the work. In the past 10 years, the Huang brothers have made a great     7     (contribute) in protecting the camellias. Even in hard times they didn’t cut down any golden camellias.

Year after year, the Huang brothers spent much time working     8     eventually made their hard work pay off. Now the golden camellia is     9     city flower of Fangchenggang. And life for the Huang brothers is greatly improved by     10     (plant) golden camellias.

7 . We are learning more and more every day about just how smart some animals are: monkeys, some species of birds, dogs, cats. But how about other animals? Snails? Mosquitos? They sure seem less smart. Still smarter than plants, though. Because it would be difficult to argue that plants are intelligent. Or would it?

In a new study, it was shown that plants send out sounds when they are sad. And these sounds are very different depending on whether they have recently been cut or whether they don’t have enough water. The sounds can’t be heard by human ears, as they are between 20 and 100 kilohertz, which is above the bottom of human hearing (which usually has the upper limit of 15-17 kilohertz).

These are fantastic results: plants don’t suffer in silence; they are screaming with pain. That is exactly what the popular science press has been doing.

There is no evidence that they are heard by anyone although theoretically (理论上) some animals — bats, moths, mice — could actually hear it as their ears are sensitive to the plant sounds. And it could very well be a byproduct (副产品) of the physical condition of these plants: less water in the system leads to more air bubbles (气泡) in plants, which leads to the sound of the popping of these bubbles.

Is this a disappointing explanation? I don’t think so. The aim is to understand why plants do what they do. And the results about the sounds contribute to this body of knowledge. They could even lead to better ways of controlling the needs of plants in gardening by sound observation.

All of this is true even if the plants don’t strictly “cry” or “scream”.

1. Why are we unable to hear the sounds of plants?

A．Because they are imagined by humans.

B．Because they go beyond human hearing.

C．Because plants don’t actually give off sounds.

D．Because plants are not as intelligent as animals.

2. What do we know about the study?

A．Plants keep silent even when they suffer.

B．Water in the plants sends off different sounds.

C．The plant sounds might show their feelings or needs.

D．The study aims to control the needs and feelings of plants.

3. Why does the author consider the explanation acceptable?

A．Because plants don’t actually “cry” or “scream”.

B．Because the results prove their knowledge of plants.

C．Because the results show that-plants understand what they do.

D．Because plants’ demands could be met by observing their sounds.

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

A．Plants suffer in silence	B．Plants “cry” in pain
C．Plants “scream” with joy	D．Plants need attention

8 . A Fish and Wildlife Service proposal would protect the whitebark pine as an endangered species. Whitebark pines can live for up to 1,000 years and grow at elevations (海拔) as high as 12,000 feet. Environmentalists had requested the government in 1991 and again in 2008 to protect the trees. A nonnative fungus (真菌) has been killing whitebark pines for a century. More recently, the trees have proved vulnerable (易受伤的) to tiny insects that have killed large areas of forest.

The whitebark pines have almost disappeared in some areas, including the eastern edge of Yellowstone National Park, where they are a source of food for threatened grizzly bears (灰熊). This makes the government’s declaration of the Yellowstone area’s grizzly bears as a restored species a lie.

After being blamed for not taking steps to protect the trees, wildlife officials in 2011 admitted that whitebark pines needed protection, but they didn’t act rapidly, saying other species faced more immediate threats.

A lawyer for the Natural Resources Defense Council, which made the formal request for protection in 2008, expressed his disappointment that it took so long but said the proposal was still worth celebrating.

The government’s proposal described the threats to the trees as immediate and said the whitebark pines were one of many plants expected to be harmed as climate change moves faster than they can adapt. “Whitebark pines survive at high elevations already, so there is little remaining habitat in many areas for the species to move to higher elevations in response to warmer temperatures,” Fish and Wildlife Service officials wrote.

Government officials are working with researchers and private groups on plans to gather seed from trees, grow them in greenhouses and then plant them back on the landscape, according to Fish and Wildlife Service biologist Amy Nicholas. A proposal of that nationwide restoration is expected by the end of this year. “We do have options to restore this species,” Nicholas said.

1. What do we know about whitebark pines?

A．They are long-lived, high-elevation trees.

B．They have a strong resistance to nonnative fungi.

C．The government used to care about protecting them.

D．They and small insects depend on each other for survival.

2. What makes the government’s announcement about grizzly bears a lie?

A．Grizzly bears are no longer threatened.

B．The whitebark pines have almost disappeared.

C．The population of grizzly bears has increased greatly.

D．The government is actually doing nothing to protect bears.

3. Which of the following would the lawyer agree with?

A．Better late than never.	B．All roads lead to Rome.
C．Never do things by halves.	D．The first step is the hardest.

4. What is Amy Nicholas’ attitude toward saving whitebark pines?

A．Irresponsible.

B．Doubtful.

C．Optimistic.

D．Uncertain.

9 . Worldwide, there are more than a thousand mistletoe (槲寄生) species. They grow on every continent except Antarctica. They are parasites(寄生物) and live on the branches of their plant “hosts”, absorbing water and nutrients to survive. They accomplish this thievery via a specialized structure that infects their hosts. In fact, they infect plants of all kinds, including themselves—a number of species have been documented parasitizing other mistletoe species.

Yet despite their parasitism, mistletoe species may well be the Robin Hoods of plants.(Robin Hood is a character in old English stories who lives in a forest with a group of friends and steals money from rich people in order to give it to poor people.) They provide food, shelter and hunting grounds for other animals. Fallen mistletoe leaves release nutrients into the forest floor that would otherwise remain locked within trees, and this generosity benefits the food chain. “Yes, ecologically, they are cheats,” says David Watson, a community ecologist at   Charles Sturt University at Albury-Wodonga, Australia. But they share their wealth. “They steal these nutrients, and then they drop them,”   Watson says.

Mistletoe species depend critically on animals to get around. Most mistletoe fruits are berries containing a single seed that’s surrounded by a sticky layer. Roughly 90 bird species are known to consume mistletoe species’ seeds, so the birds can pass them to other trees on their bodies, or when they are eaten, seeds are passed through their waste. (There are exceptions:   Some mistletoe species make explosive fruits that send their seeds toward nearby trees,   reaching distances of 10 meters or more.)

Scientists have known that mistletoe species all have ancestors that were parasites not on branches, but on roots.   “They evolved over and over and over, and this understory,   root-parasitic, shrubby thing switched to being an aerial(meaning they infect above-ground plant parts, rather than roots), parasitic shrubby thing,” Watson says. Moving up the tree helped to solve a problem that all plants are faced with: competing for sunlight. Despite their parasitic nature, most mistletoe species still use energy from light to make their food.

1. What can we learn about mistletoe species according to paragraph 1?

A．They are highly independent.	B．They are harmful to their hosts.
C．They can be found on every continent.	D．They prefer to live on the roots of plants.

2. In what way are mistletoe species similar to Robin Hood?

A．They help poorly grown trees absorb more nutrients.

B．They have remarkable abilities to survive in the forest.

C．They live in the forest with other plant species in groups.

D．They steal and give food to many other living things.

3. How do most mistletoe species spread their seeds?

A．With the help of birds.	B．By making explosive fruits.
C．With the help of nearby trees.	D．By taking advantage of hosts’ seeds.

4. What does Watson tell us about the evolutionary development of mistletoe species?

A．They eventually evolved into shrubby plants.

B．Their habitats changed from roots to branches.

C．They tried to give up using energy from sunlight.

D．Their parasitic nature was formed in a gradual way.

10 . After tracking flowers on a prairie (草原) in Minnesota for 21 years, scientists reported that the plants reproduce more successfully in the year following a carefully controlled burn. Understanding the relationship between prairie plants and fire is important for preserving this ecosystem which is becoming rapidly smaller, says Stuart Wagenius, a conservation scientist.

Fire provides an additional advantage for the narrow-leaved purple coneflower (紫锥花), as Wagenius and his colleagues say. To really bloom (开花), they need a little help: Enter the fire. Between 1996 and 2016, Wagenius says his team tracked nearly 8,000 purple coneflowers on the Staffanson Prairie Preserve. In 9 of those years, they conducted controlled burns over 400 times. “In the summer after a burn, many more plants flower,” Wagenius says. “It is just a huge flowering festival.”

Purple coneflowers and many other prairie plants were previously known to bloom energetically after fires. However, the researchers said that fire also stimulated purple coneflowers to bloom at the same time in the summer after a burn. This meant that instead of being unconnected, the purple coneflowers were surrounded by potential mates and went on to produce nearly double the number of seeds compared with other years. Wagenius says it’s not yet clear exactly how fires signal the flowers to get busy.

The new findings may help the people who manage prairies to better understand the different ways that fire affects the plants growing in these habitats, said Kathryn Yurkonis, a grassland ecologist who was not involved in the research. However, Yurkonis added, it remains to be shown how the fires influence the purple coneflower population. “This paper implies that making more seeds would mean more seeds would land on the soil and enter the population of plants — but they don’t actually examine that step,” she said. “I’d be curious to see whether this actually translates to more purple coneflowers.”

1. What is the basis for the research?

A．Prairies are easy to disappear.	B．Plants on a prairie are diverse.
C．Fire relates positively to prairie plants.	D．Without fire, flowers won’t bloom.

2. What does the author intend to convey with figures cited in paragraph two?

A．Wagenius’s team was committed indeed.

B．Samples of flowers were rich in number.

C．Time spent on the research was long.

D．The findings were relatively convincing.

3. What is paragraph 3 mainly about?

A．The result of plants being unconnected.

B．The influence of fires on prairie plants.

C．The process of prairie plants’ growing after fires.

D．The reason for plants’ blooming at the same time.

4. What is Kathryn Yurkonis’s attitude to the research finding?

A．Uninterested.

B．Prejudiced.

C．Objective.

D．Opposed.