1 . When John Todd was a child, he loved to explore the woods around his house, observing how nature solved problems. A dirty stream, for example, often became clear after flowing through plants and along rocks where tiny creatures lived. When he got older, John started to wonder if this process could be used to clean up the messes people were making.
After studying agriculture, medicine, and fisheries in college, John went back to observing nature and asking questions. Why can certain plants trap harmful bacteria (细菌)? Which kinds of fish can eat cancer-causing chemicals? With the right combination of animals and plants, he figured, maybe he could clean up waste the way nature did. He decided to build what he would later call an eco-machine.
The task John set for himself was to remove harmful substances from some sludge (污泥). First, he constructed a series of clear fiberglass tanks connected to each other. Then he went around to local ponds and streams and brought back some plants and animals. He placed them in the tanks and waited. Little by little, these different kinds of life got used to one another and formed their own ecosystem. After a few weeks, John added the sludge.
He was amazed at the results. The plants and animals in the eco-machine took the sludge as food and began to eat it! Within weeks, it had all been digested, and all that was left was pure water.
Over the years, John has taken on many big jobs. He developed a greenhouse — like facility that treated sewage (污水) from 1,600 homes in South Burlington. He also designed an eco-machine to clean canal water in Fuzhou, a city in southeast China.
“Ecological design” is the name John gives to what he does. “Life on Earth is kind of a box of spare parts for the inventor,” he says. “You put organisms in new relationships and observe what’s happening. Then you let these new systems develop their own ways to self-repair.”
1. What can we learn about John from the first two paragraphs?A.He was fond of traveling. | B.He enjoyed being alone. |
C.He had an inquiring mind. | D.He longed to be a doctor. |
A.To feed the animals. | B.To build an ecosystem. |
C.To protect the plants. | D.To test the eco-machine. |
A.To review John’s research plans. | B.To show an application of John’s idea. |
C.To compare John’s different jobs. | D.To erase doubts about John’s invention. |
A.Nature can repair itself. | B.Organisms need water to survive. |
C.Life on Earth is diverse. | D.Most tiny creatures live in groups. |
2 . Indoor plants might look as if they just sit around not doing much, but in many ways they are the unsung heroes of the home.
What are indoor plants?
Indoor plants, also known as houseplants or pot plants, are plants that like to grow indoors. Many of these species (物种) are not ideally suited to growing outside in the UK, especially in the winter.
Why are indoor plants good for you?
Will Spoelstra, who works at the Royal Botanic Gardens, says, “
Which plants can you grow?
Aloe vera, peace lilies and spider plants are some of the species that are easy to grow indoors. You can buy plants from supermarkets, garden centres or online. Younger plants are often cheaper than fully grown ones, and you get to care for them as they mature — which is part of the joy of owning plants. “
A.All plants are different |
B.Not only do they look beautiful |
C.There are many benefits to growing plants indoors |
D.Instead, they grow better inside, where it is warmer |
E.Plants like peace lilies and devil’s ivy are among the best |
F.Changing the pot of your plant from time to time will also help |
G.Learning about the requirements of each plant can be very rewarding |
A visually-challenged man from Beijing recently hiked (徒步) 40 days to Xi’an, as a first step
On the 1,100 kilometer journey, the man Cao Shengkang,
Cao and Wu also collected garbage along the road, in order to promote environmental
In the last five years. Cao
Now, Cao has started the second part of his dream to walk along the Belt and Road route. He flew 4, 700 kilometers
4 . The connection between people and plants has long been the subject of scientific research. Recent studies have found positive effects. A study conducted in Youngstown,Ohio,for example, discovered that greener areas of the city experienced less crime. In another,employees were shown to be 15% more productive when their workplaces were decorated with houseplants.
The engineers at the Massachusetts Institute of Technology(MIT)have taken it a step further changing the actual composition of plants in order to get them to perform diverse,even unusual functions. These include plants that have sensors printed onto their leaves to show when they’re short of water and a plant that can detect harmful chemicals in groundwater. "We’re thinking about how we can engineer plants to replace functions of the things that we use every day,"explained Michael Strano, a professor of chemical engineering at MIT.
One of his latest projects has been to make plants glow(发光)in experiments using some common vegetables. Strano’s team found that they could create a faint light for three-and-a-half hours. The light,about one-thousandth of the amount needed to read by,is just a start. The technology, Strano said, could one day be used to light the rooms or even to turn trees into self-powered street lamps.
In the future,the team hopes to develop a version of the technology that can be sprayed onto plant leaves in a one-off treatment that would last the plant’s lifetime. The engineers are also trying to develop an on and off"switch"where the glow would fade when exposed to daylight.
Lighting accounts for about 7% of the total electricity consumed in the US. Since lighting is often far removed from the power source(电源)-such as the distance from a power plant to street lamps on a remote highway-a lot of energy is lost during transmission(传输).Glowing plants could reduce this distance and therefore help save energy.
1. What is the first paragraph mainly about?A.A new study of different plants. |
B.A big fall in crime rates. |
C.Employees from various workplaces. |
D.Benefits from green plants. |
A.To detect plants’ lack of water |
B.To change compositions of plants |
C.To make the life of plants longer. |
D.To test chemicals in plants. |
A.They will speed up energy production. |
B.They may transmit electricity to the home. |
C.They might help reduce energy consumption. |
D.They could take the place of power plants. |
A.Can we grow more glowing plants? |
B.How do we live with glowing plants? |
C.Could glowing plants replace lamps? |
D.How are glowing plants made pollution-free? |
5 . I have worked as a keeper at the National Zoo, Paris for 11 years. Spot and Stripe are the first tiger cubs that have ever been born here. Globally, a third of Sumatran cubs in zoos don't make it to adulthood, so I decided to give them round-the-clock care at home.
I've got two children—the younger one, Kynan, was extremely happy about the tigers arriving - but all of us really looked forward to being part of their lives and watching them grow. I wasn't worried about bringing them into my home with my wife and kids. These were cubs. They weighed about 2.5 kg and were so small that there was absolutely no risk.
As they grew more mobile, we let them move freely around the house during the day, but when we were asleep we had to contain them in a large room, otherwise they'd get up to mischief. We'd come down in the morning to find they'd turned the room upside down, and left it looking like a zoo.
Things quickly got very intense due to the huge amount of energy required to look after them. There were some tough times and I just felt extremely tired. I was grateful that my family was there to help. We had to have a bit of a production line going, making up “tiger milk”, washing baby bottles, and cleaning the floors.
When Spot and Stripe were four months old, they were learning how to open doors and jump fences, and we knew it really was time for them to go. It was hard for us to finally part with them. For the first few days, Kynan was always a bit disappointed that the cubs weren't there.
I'm not sad about it. I'm hands-on with them every day at the zoo, and I do look back very fondly on the time that we had them.
1. Why did the author bring the tiger cubs home?A.To ensure their survival. | B.To observe their differences. |
C.To teach them life skills. | D.To let them play with his kids. |
A.Behave badly. | B.Lose their way. | C.Sleep soundly. | D.Miss their mom. |
A.Boring. | B.Tiring. | C.Costly. | D.Risky. |
A.They frightened the children. | B.They became difficult to contain. |
C.They annoyed the neighbours. | D.They started fighting each other. |
6 . Researchers say they have translated the meaning of gestures that wild chimpanzees (黑猩猩) use to communicate. They say wild chimps communicate 19 specific messages to one another with a “vocabulary” of 66 gestures. The scientists discovered this by following and filming groups of chimps in Uganda, and examining more than 5,000 incidents of these meaningful exchanges.
Dr Catherine Hobaiter, who led the research, said that this was the only form of intentional communication to be recorded in the animal kingdom. Only humans and chimps, she said, had a system of communication where they deliberately sent a message to another group member.
“That’s what’s so amazing about chimp gestures,” she said. “They’re the only thing that looks like human language in that respect.”
Although previous research has shown that apes and monkeys can understand complex information from another animal’s call, the animals do not appear to use their voices intentionally to communicate messages. This was a significant difference between calls and gestures, Dr Hobaiter said.
Chimps will check to see if they have the attention of the animal with which they wish to communicate. In one case, a mother presents her foot to her crying baby, signaling: “Climb on me.” The youngster immediately jumps on to its mothers back and they travel off together. “The big message from this study is that there is another species (物种) out there. that is meaningful in its communication, so that’s not unique to humans,” said Dr Hobaiter.
Dr Susanne Shultz, an evolutionary biologist from the University of Manchester, said the study was praiseworthy in seeking to enrich our knowledge of the evolution of human language. But, she added, the results were “a little disappointing”.
“The vagueness of the gesture meanings suggests either that the chimps have little to communicate, or we are still missing a lot of the information contained in their gestures and actions,” she said. “Moreover, the meanings seem to not go beyond what other animal convey with non-verbal communication. So, it seems the gulf remains. ”
1. What do chimps and humans have in common according to Dr Hobaiter?A.Memorizing specific words. | B.Understanding complex information. |
C.Using voices to communicate. | D.Communicating messages on purpose. |
A.It was well designed but poorly conducted. |
B.It was a good try but the findings were limited. |
C.It was inspiring but the evidence was unreliable. |
D.It was a failure but the methods deserved praise. |
A.Difference. | B.Conflict. | C.Balance. | D.Connection. |
A.Chimpanzee behaviour study achieved a breakthrough |
B.Chimpanzees developed specific communication skills |
C.Chimpanzees: the smartest species in the animal kingdom |
D.Chimpanzee language: communication gestures translated |
7 . Washington, D.C. Bicycle Tours
Cherry Blossom Bike Tour in Washington, D.C.
Duration: 3 hours
This small group bike tour is a fantastic way to see a world-famous cherry trees with beautiful flowers of Washington, D.C. Your guide will provide a history lesson about the trees and the famous monuments where they blossom. Reserve your spot before availability — the cherry blossoms—disappear!
Washington Capital Monuments Bicycle Tour
Duration: 3 hours (4 miles)
Join a guided bike tour and view some of the most popular monuments in Washington, D.C. Explore the monuments and memorials on the National Mall as your guide shares unique facts and history at each stop. Guided tour includes bike, helmet, cookies and bottled water.
Capital City Bike Tour In Washington, D.C.
Duration: 3 hours
Morning or Afternoon, this bike tour is the perfect tour for D. C. newcomers and locals looking to experience Washington, D.C. in a healthy way with minimum effort. Knowledgeable guides will entertain you with the most, interesting stories about Presidents, Congress, memorials, and parks. Comfortable bikes and a smooth tour route(路线) make cycling between the sites fun and relaxing.
Washington Capital Sites at Night Bicycle Tour
Duration: 3 hours (7miles)
Join a small group bike tour for an evening of exploration in the heart of Washington, D.C. Get up close to the monuments and memorials as you bike the sites of Capitol Hill and the National Mall. Frequent stops are made for photo taking as your guide offers unique facts and history. Tour includes bike, helmet, and bottled water. All riders are equipped with reflective vests and safety lights.
1. Which tour do you need to book in advance?A.Cherry Blossom Bike Tour in Washington, D.C. |
B.Washington Capital Monuments Bicycle Tour. |
C.Capital City Bike Tour in Washington. |
D.Washington Capital Sites at Night Bicycle Tour. |
A.Meet famous people. | B.Go to a national park. |
C.Visit well-known museums. | D.Enjoy interesting stories. |
A.City maps. | B.Cameras. |
C.Meals. | D.Safety lights. |
8 . California has lost half its big trees since the 1930s, according to a study to be published Tuesday and climate change seems to be a major factor(因素).
The number of trees larger than two feet across has declined by 50 percent on more than 46, 000 square miles of California forests, the new study finds. No area was spared or unaffected, from the foggy northern coast to the Sierra Nevada Mountains to the San Gabriels above Los Angeles. In the Sierra high country, the number of big trees has fallen by more than 55 percent; in parts of southern California the decline was nearly 75 percent.
Many factors contributed to the decline, said Patrick McIntyre, an ecologist who was the lead author of the study. Woodcutters targeted big trees. Housing development pushed into the woods. Aggressive wildfire control has left California forests crowded with small trees that compete with big trees for resources(资源).
But in comparing a study of California forests done in the 1920s and 1930s with another one between 2001 and 2010, McIntyre and his colleagues documented a widespread death of big trees that was evident even in wildlands protected from woodcutting or development.
The loss of big trees was greatest in areas where trees had suffered the greatest water shortage. The researchers figured out water stress with a computer model that calculated how much water trees were getting in comparison with how much they needed, taking into account such things as rainfall, air temperature, dampness of soil, and the timing of snowmelt(融雪).
Since the 1930s, McIntyre said, the biggest factors driving up water stress in the state have been rising temperatures, which cause trees to lose more water to the air, and earlier snowmelt, which reduces the water supply available to trees during the dry season.
1. What is the second paragraph mainly about?A.The seriousness of big-tree loss in California. |
B.The increasing variety of California big trees. |
C.The distribution of big trees in California forests. |
D.The influence of farming on big trees in California. |
A.Ecological studies of forests. |
B.Banning woodcutting. |
C.Limiting housing development. |
D.Fire control measures. |
A.Inadequate snowmelt. | B.A longer dry season. |
C.A warmer climate. | D.Dampness of the air. |
A.California’s Forests: Where Have All the Big Trees Gone? |
B.Cutting of Big Trees to Be Prohibited in California Soon |
C.Why Are the Big Trees Important to California Forests? |
D.Patrick McIntyre: Grow More Big Trees in California |
A Tsinghua professor is leading authority on tackling global warming and public attention has been drawn
Global warming, carbon footprints, the 2-degree limitation for temperature
In addition to his academic research and teaching work, the climate change economics professor from the Department of Earth System Science at Tsinghua University,has made a speech to
“I’m a strong believer in environmental protection
His speech last year on I Am A Scientist, a multiplatform series of online articles and videos organized by the China Association for Science and Technology,
“Since the industrial revolution, the burning of fossil fuels
In 2000, he chose
10 . It’s unlikely that we’ll see a dodo, a flightless bird, walking this earth anytime again, according to Beth Shapiro, a evolutionary molecular biologist.
“When most people think about de-extinction, they’re imagining cloning,” Shapiro said. Cloning, the approach that created Dolly, the sheep in 1996 and Elizabeth Ann, the black-footed ferret in 2020, creates an identical genetic copy of an individual by putting DNA from a living adult cell into an egg cell from which the nucleus (细胞核) has been removed. Adult cells contain all the DNA needed to develop into a living animal. Egg cells then use that DNA as a blueprint to turn themselves into many kinds of cells——skin, organs, blood and bones——the animal needs.
“But no living cells from dodos exist. Instead,” Shapiro said, “you’d have to start with a closely related animal’s genome (基因组) and then change it into one similar to dodos.” For example, mammoths (猛犸) are also extinct,but they were very closely related to modern Asian elephants, so researchers are attempting to bring mammoths back from extinction by creating a hybrid mammoth with some mammoth genes replacing part of the elephant genome in an elephant egg cell. However, there are likely millions of genetic differences between the genome of an Asian elephant and that of a mammoth according to Shapiro.
As for the dodo, its closest living relative is the Nicobar pigeon. Mammoths and Asian elephants are pretty closely related, whereas it had been more than 20 million years since the dodo and the Nicobar pigeon had any common ancestors. Genetic differences between the two bird species are therefore much greater, making it a formidable task to create a successful hybrid in the lab, Shapiro said.
Even if scientists manage to bring dodos back, the island where they once lived is a very different place nowadays, which make it impossible to reintroduce dodos without major intervention.
1. What is Paragraph 2 mainly about?A.The special role of DNA. |
B.The process of cloning. |
C.The development of cloning. |
D.The complexity of cloning. |
A.Dodos are harder to bring back to life. |
B.Their living cells are hard to preserve. |
C.Cloning can be used to recreate extinct animals. |
D.They share a similar genome with Asian elephants. |
A.Urgent. |
B.Possible. |
C.Tough. |
D.Different. |
A.Favorable. |
B.Intolerant. |
C.Objective. |
D.Negative. |