1 . Common water plant could provide a green energy source. Scientists have figured out how to get large amounts of oil from duckweed, one of nature’s fastest-growing water plants. Transferring such plant oil into biodiesel (生物柴油) for transportation and heating could be a big part of a more sustainable future.

For a new study, researchers genetically engineered duckweed plants to produce seven times more oil per acre than soybeans. John Shanklin, a biochemist says further research could double the engineered duckweed’s oil output in the next few years.

Unlike fossil fuels, which form underground, biofuels can be refreshed faster than they are used. Fuels made from new and used vegetable oils, animal fat and seaweed can have a lower carbon footprint than fossil fuels do, but there has been a recent negative view against them. This is partly because so many crops now go into energy production rather than food; biofuels take up more than 100 million acres of the world’s agricultural land.

Duckweed, common on every continent but Antarctica, is among the world’s most productive plants, and the researchers suggest it could be a game-changing renewable energy source for three key reasons. First, it grows readily in water, so it wouldn’t compete with food crops for agricultural land. Second, duckweed can grow fast in agricultural pollution released into the water. Third, Shanklin and his team found a way to avoid a major biotechnological barrier: For the new study, Shanklin says, the researchers added an oil-producing gene, “turning it on like a light switch”by introducing a particular molecule (分子) only when the plant had finished growing. Shanklin says, “If it replicates (复制) in other species-and there’s no reason to think that it would not — this can solve one of our biggest issues, which is how we can make more oil in more plants without negatively affecting growth.”

To expand production to industrial levels, scientists will need to design and produce large-scale bases for growing engineered plants and obtaining oil — a challenge, Shanklin says, because duckweed is a non-mainstream crop without much existing infrastructure (基础设施).

1. What can people get from duckweed firsthand?

A．Plant oil.	B．Stable biodiesel.
C．Sustainable water.	D．Natural heat.

2. What does paragraph 4 mainly convey?

A．Options for renewable energy.

B．Reasons for engineering genes.

C．The potential of revolutionary energy source.

D．The approach to avoiding agricultural pollution.

3. What is the decisive factor to mass-produce the plant?

A．Industrial levels.	B．Unique design.
C．Academic research.	D．Basic facilities.

4. What would be the best title for the text?

A．Duckweed Power	B．Duckweed Production
C．Genetic Engineering	D．Genetic Testing

2 . Gotham Greens started as a single rooftop (外屋顶) greenhouse in Brooklyn. New York City. Now, it is one of the largest greenhouse lettuce (生菜) producers in North America, with soon-to-be 13 sites across nine states.

“Ninety-nine percent of the food that we eat in New York City has to be brought in from other places and has to travel very far. For example, lettuce like this usually comes from places like California that are 3,000 miles away.” explains Chief Executive Officer Viraj Puri.

The company plans to grow 100 million heads of lettuce this year. Puri founded Gotham Greens because he wanted to bring farms close to the communities they serve. For example, the lettuce grown on the roof on Third Street in Gowanus only needs to be transported down using a lift to reach the supermarket Whole Foods.        

Many people might not think of New York City as a place to grow produce, but rooftop farms can be easily found in the city. “Here, it’s about 70 degrees and the plants are growing well because we are creating the perfect growing conditions for them,“ Puri explains.

Grown completely in water in renewably-powered greenhouses, the farms use less water and land. “The plants are grown in water to which nutrients (营养物) are added, making them grow very quickly. We can avoid the use of chemicals (化学品),” says Puri.

The company also donates (捐赠) tens of thousands of young plants a year to organizations that work to feed people and provide educational programming around city farming. In the Claremont Village area of the Bronx, local students like 16-year-old Jill Bonilla care for towers of herbs and vegetables in a unique classroom.

”Plants don’t take that long to grow; you just got to take care of them properly,“ she says. ”It helps me stay healthy and stay away from junk food.“

Bonilla and hundreds of other kids are part of the educational organization Green Bronx Machine, which partners with Gotham Greens to educate students. Green Bronx Machine’s programs are in 675 schools across the country. Last year, it grew more than 8,000 pounds of food in the Bronx, and donated 150,000 pounds of healthy produce.

1. What can we learn from paragraphs 2 and 3?

A．Most of New York City’s lettuce comes from Brooklyn.

B．Rooftop farms are becoming popular in New York City.

C．Planting lettuce in New York City makes a big difference.

D．Gotham Greens was founded to make New York City greener.

2. What does paragraph 5 mainly tell us about rooftop farms?

A．Their numbers are growing rapidly.

B．They are environmentally friendly.

C．Their market has already opened up.

D．They are less costly than traditional farms.

3. What does Bonilla say about studying in the special classroom?

A．It is worth the time.

B．It is a bit challenging.

C．It has built up her confidence,

D．It has changed her ideas about farmers.

4. What do Gotham Greens and Green Bronx Machine have in common?

A．They support poor students.

B．They have their own schools.

C．They run educational programs.

D．They have farms in the countryside.

3 . How to Save Money Watering Your Garden

Jessica Damiano writes about gardening. In her latest story, she talks about cost-saving ways to keep your garden watered during the hot months of summer. Let’s look at some of Damiano’s recommendations.

Know when and how to water

    1    . This lets the water go deeply into the soil before the weather gets too hot. If you water later in the day, the water will just evaporate(蒸发)from the surface. If you water in the evening, the plants stay too wet overnight.

How you water is just as important as when you water. If you water quickly every day, it does not help the roots, which can extend over 30 centimeters into the soil.     2    .

Catch and reuse water

You can recycle water from boiling vegetables or eggs. Just make sure the water does not have salt in it.     3    . Redirect a pipe that collects rainwater to fill a large container, then use the container to refill watering cans or connect a hose(软管)to a hole at the bottom of the container.

    4    

Most gardeners just think about which plants look good and the plants’ sunlight needs. But watering needs should be considered, too. Drought-resistant plants should not be overwatered. It is best to use plants that are native to the area where you live. These plants tend to be resistant to drought. They just need regular watering in their first two years.     5    .

A．Choose native plants

B．Instead, water the soil less often, but deeply

C．The best time to water plants is in the morning

D．It is also good practice to catch and use rainwater

E．This helps make the cities greener and improve air quality

F．Give some thought to how many plants there are in your garden

G．After that, they can live on just rainwater except during heat waves

4 . Seagrass meadows(海草床) are wonder plants growing beneath the sea. They feed and shelter sea life and are masterful at storing carbon. Thanks to the assistance of tiger sharks, a huge seagrass meadow in the Bahamas Banks was recently discovered, offering the world a tool to fight climate change.

Seagrass has usually been detected by Earth-orbiting satellites that identify darker patches in the blue water. In this study, tiger sharks were selected as research tools due to their highly consistent associations with seagrass ecosystems. They spend 70% of their time in seagrass meadows. The team equipped eight tiger sharks with satellite tags (电子跟踪器), seven sharks with camera tags, and used a 360-degree camera on a shark for the first time ever.

The data researchers collected was astonishing. The world’s largest seagrass ecosystem, measuring at least 66,900 square kilometers, has been discovered. This reflects a 41% increase from previous estimates of global seagrass. Seagrass can capture (捕获) huge quantities of carbon by photosynthesis (光合作用) and stores it on the seafloor. In terms of climate change, this is excellent news; seagrass is 35 times faster a removing carbon than tropical rainforests. When referred to global seagrass carbon stock estimates, the study indicates that seagrass in the Bahamas may contain 19.2% to 26.3% of all the carbon stored in seagrass meadows on Earth.

Yet seagrass meadows are rapidly disappearing, with over 92% of meadows in the UK gone, according to the World Wildlife Fund. Scientists are collecting seeds and trying to grow new seagrass meadows through restoration projects. This new discovery offers optimism and proves the importance of the ocean for healing.

The sharks led us to the seagrass ecosystem in the Bahamas, which we now know is likely the most significant blue carbon sink(蓝色碳汇) on the planet. What this discovery shows us is that ocean exploration and research are essential for a healthy future. The untapped potential of the ocean is limitless. These meadows can be protected and can be replicated (复制,仿制), offering hope for climate change around the globe.

1. Why were tiger sharks chosen as research tools?

A．They are more flexible than other sea animals.

B．They can quickly adjust themselves to the deep sea.

C．They have a strong connection with seagrass ecosystems.

D．They can be easily equipped with experimental devices.

2. What are the numbers in paragraph 3 mainly about?

A．The decline of global seagrass meadows.

B．The impact of climate change on sea life.

C．The rapid increase in the amount of carbon on Earth.

D．The potential value of the world’s largest seagrass ecosystem.

3. What are scientists doing to protect seagrass?

A．Planting more seagrass meadows.

B．Developing new technology to collect seeds.

C．Mapping the distribution of seagrass meadows.

D．Encouraging people to join in restoration projects.

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

A．The New Way of Removing Carbon

B．The Significance of Ocean Exploration

C．A New Discovery: World’s Largest Seagrass Meadow

D．Tiger Sharks: Scientists’ Essential Helper to Study Climate

5 . How to Start Gardening

If you are feeling the itch(渴望) to get a green thumb and start gardening, we cannot blame you.    1    So, let’s get you on the way to starting your own gardening that is right for you!

The first step is to come up with an idea of what you want to grow. If you are going to grow a crop, make sure it is something you will eat. You also need to make sure your area has the right climate, and that you are planting at the right time. Most plants will require planting in spring, but sometime planting in the fall,so make sure you know the life cycle of a plant and when you should plant it.    2    

After you have chosen what you want to grow, picture your garden or even draw up a plan. Look at what will go where depending on how much sun it needs.     3    Think about walls and fences and how they will impact the suns’ placement in your garden. You should also think about access for watering, picking and nurturing your plants.

Testing your soil is necessary.     4    A majority of crops in your garden will need neutral pH 7 soil. If the soil is not nutritious enough, consider fertilizer on a more regular basis. Always find out what kind of soil the plant needs first and then supply the correct soil to the correct plant.

    5    You should always make sure that you choose the right seeds before you start planting. It is wise to learn which plants will grow best when directly seeded in the garden and which plants are better as transplanted plants. Then it is time to get planting.

A．Choose the right seeds and then plant them.

B．It has so many benefits and it is hard to resist.

C．You should also look up a seeding calendar as well.

D．Consider the sun in the sky above your garden as well.

E．And keep the kids’ play area away from the planting areas.

F．Many green hands to the gardening scene do not know this.

G．It is also worth looking into what grows well in your local area and what doesn’t.

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。

Hua Weiguang,     1     retired teacher from Tongliao, Inner Mongolia Autonomous Region, is a photography enthusiast.

A decade ago, the arrival of tree planters     2     (catch) Hua’s attention and the photos of the tree planters     3     (take) by Hua are evidence of the     4     (remark) transformation of the land. In those photos, hats, scarves and goggles, for the workers fighting desertification, are basic necessities to protect them     5     the wind and sand. There was no way to avoid the brutal summer heat in the land so the workers had to lie down on the ground or curl up in the narrow shade of their cars to cool off. And they also had to eat their lunch amid the blowing sands, taking in the small pieces of sand with their food.

“    6     we don’t fool the tree, it won’t fool you. You take it     7     (serious), and then it behaves in the same way to you. You put efforts to make it live, and the tree lives up to your     8     (expect),” the planters say.

China’s forest resources have increased by over 70 million hectares in the past decade,     9     (rank) first in the world. One tree after another, a green Great Wall has been built. Brush by brush, a green field     10     (paint) over the yellow sandy land up to now.

7 . The rapid pace of global warming and its effects on habitats raise the question of whether species are able to keep up so that they remain in suitable living conditions. Some animals can move fast to adjust to a swiftly changing climate. Plants, being less mobile, rely on means such as seed dispersal(传播) by animals, wind or water to move to new areas, but this redistribution typically occurs within one kilometre of the original plant.

When the climate in a plant’s usual range becomes hotter than it can tolerate, it must find new, cooler areas that might lie many kilometres away. One explanation for long-distance seed dispersal is through transport by migratory (迁徙的) birds. Such birds swallow seeds when eating fruit and can move them tens or hundreds of kilometres outside the range of a plant species.

Gonzáiez-Vary and colleagues report how plants might be able to keep pace with rapid climate change with the help of migratory birds. The authors analysed the fruiting times of plants, patterns of bird migration and the interactions between fruit-eating birds and fleshy-fruited plants across Europe. Plants with fleshy fruits were chosen for this study because most of their seed transport is by migratory birds, and because fleshy-fruited plants are an important part of the woody-plant community in Europe. The common approach until now has been to predict plant dispersal using models fitted to abiotic (非生物的) factors such as the current climate. Gonzáiez-Vary instead analysed an impressive data set of 949 different seed-dispersal interactions between bird and plant communities, together with data on entire fruiting times and migratory patterns of birds across Europe. The researchers also analysed DNA traces from bird wastes to identify the plants and birds responsible for seed dispersal.

1. How do species adapt to climate changes when it’s too hot?

A．All animals will move away across great distanced.

B．Some plants depend on migratory birds to carry seeds.

C．Some plants depend on animals, wind or water to move.

D．Plants’ seeds disperse to cooler places of several kilometres away.

2. Why did researchers mainly study fleshy-fruited plants?

A．Most of these can’t fit rapid climate change

B．Migratory birds like making nests in them

C．Migratory birds transport their seeds.

D．They are favoured by most birds.

3. Why does the author mention “fleshy fruits” and “fruiting times” in paragraph 3?

A．To explain relations between fruit plants and migratory birds.

B．To clarify the reason why birds migrate in fruiting times.

C．To present a fact that migratory bird eats flesh fruits.

D．To show that fruits depend on migratory birds.

4. What is the text mainly about?

A．The advantage of fruit plants.

B．The destination of the bird migration.

C．The adaptation of fruit plants to the climate change.

D．The influence of climate change on plants and animals.

8 . “How many of us as children have stared up at a church-like top of a giant tree and climbed it in wonder, which is a rally special part of our lives?” asks Bill Laurance, a tropical ecologist at James Cook University. “The leaves of big trees in forests are spreading out in all directions. We’re faced with organisms that have evolved for long periods of ecological stability.”

“There’s a lot to discuss on the issue,” says David Lindenmayer, a conservation ecologist at the Australian National University. “Climate change will mean that, in some forests, big trees won’t reach the same sizes they used to.” The effects of climate change, including long droughts, more invasive species and so on increase the simple physical challenges that big trees face in pulling water from their roots to their leaves and withstanding windstorms.

Lindenmayer and Laurance define “large, old trees” as the largest five percent mature trees within a species. The flexible definition means that in some forests, the large, old trees might be only 20 meters tall and 100 years old.

These large, old trees control the surrounding plant communities, affect water and nutrient distribution, and provide food and shelter for wildlife. “They’re really the breadbaskets of the forest,” says Laurance. “This is a very environmentally and ecologically important group of organisms, and they need special care and handling.” Determining the distribution and habitat requirements for large, old trees in the landscape is the first step towards ensuring their survival, “We have to ensure that what we’re thinking is long-term, to match the way these trees have existed for hundreds or even thousands of years,” says Laurance. “It’s going to be a real challenge to keep some places where there is still wildlife and the big church-like trees that we all really care about.”

1. How does the author lead in the topic of the text?

A．By definition.	B．By comparison.
C．By quoting someone’s words.	D．By drawing some conclusions.

2. What can we learn about big trees from paragraph 2?

A．They are affected by various factors.

B．They have become shorter but thicker.

C．They easily pull water from their roots.

D．They grow taller because of climate change.

3. Which of the following does Laurance want to express in the last paragraph?

A．The plants around control trees’ survival.

B．It is necessary to take good care of big trees.

C．Big trees mainly depend on wildlife for survival.

D．Planting big trees is the first step in forest protection.

4. What can be the best title for the text?

A．Protect Forest Giants

B．Keep Ecological Stability

C．Deal with Forest Organisms

D．Fight Against Climate Change

9 . Plants are our useful companions on Earth. They consume carbon dioxide and release oxygen, provide us with dietary and medicinal products and brighten up our environment. However, they are the victims of circumstances. Planted in an adequately sunny spot and provided with water they thrive (茁壮成长). However, put in unfortunate conditions, they have no choice but to wither (枯萎) and die. Bu what if plants could relocate to better places?

It was this question that Sun Tianqi, founder of a Chinese robotics firm Vincross, asked himself while watching a dead sunflower. "I thought if it could have taken a 30-foot walk out of the shadow to where the other sunflowers were, it would have lived healthily," he said.

He decided then to build a robot that would let plants do just that. The innovative roboticist took one of his company's traditional HEXA robot models and built a "flowerpot," which replaced HEXA's shell.

According to its site, HEXA is a "six-legged robot that comes complete with all the necessary sensors." The result is an impressive plant robot that can chase (追逐) the sun, hide for shelter, interact with humans when tapped and perform a funny dance to indicate it is thirsty.

Although the plant robot may have many useful future applications, Tiangi's reasons for creating it seem to have been philosophical. "Plants are passive. No matter if they are being cut, bitten, burned or pulled from the earth, or when they lack sunshine, water, or are too hot or cold, they will hold still and take whatever is happening to them," he said. "They have the fewest degrees of freedom among all the creatures in nature. This is simply the setting that nature gives to plants. I do hope that this project can bring some inspiration to the relationship between technology and unfavorable natural settings," concluded Tianqi.

1. What information is implied in the underlined sentence in paragraph 1？

A．Plants need great care to grow well.

B．Plants are used for many purposes

C．Plants have a life cycle like humans.

D．Plants are important to the environment

2. What inspired Tiangi to build a plant robot?

A．His environmental awareness.	B．His love for sunflowers.
C．A broken flowerpot.	D．A dead flower.

3. What do we know about the plant robot?

A．It is solar-powered.	B．It enables plants to move.
C．It feeds nutrients to plants.	D．It offers growers useful tips

4. What did Tianqi try to convey by the words in the last paragraph

A．His robot needs much improvement.

B．Technology can set human beings free.

C．His robot has many useful future applications.

D．Technology can remove natural disadvantages.