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.”

2 . Turning soil, pulling weeds, and harvesting cabbage sound like tough work for middle and high school kids. And at first it is, says Abby Jaramillo, who with another teacher started Urban Sprouts, a school garden program at four low-income schools. The program aims to help students develop science skills, environmental awareness, and healthy lifestyles.

Jaramillo’s students live in neighborhoods where fresh food and green space are not easy to find and fast food restaurants outnumber grocery stores. “The kids literally come to school with bags of snacks and large bottles of soft drinks,” she says. “They come to us thinking vegetables are awful, dirt is awful, insects are awful.” Though some are initially scared of the insects and turned off by the dirt, most are eager to try something new.

Urban Sprouts’ classes, at two middle schools and two high schools, include hands-on experiments such as soil testing, flower-and-seed dissection, tastings of fresh or dried produce, and work in the garden. Several times a year, students cook the vegetables they grow, and they occasionally make salads for their entire schools.

Program evaluations show that kids eat more vegetables as a result of the classes. “We have students who say they went home and talked to their parents and now they’re eating differently,” Jaramillo says.

She adds that the program’s benefits go beyond nutrition. Some students get so interested in gardening that they bring home seeds to start their own vegetable gardens. Besides, working in the garden seems to have a calming effect on Jaramillo’s special education students, many of whom have emotional control issues. “They get outside,” she says, “and they feel successful.”

For thousands of years, people have told fables (寓言)     1     (teach) a lesson or to pass on wisdom. Fables were part of the oral tradition of many early cultures, and the well-known Aesop’s fables date to the     2     (six) century, B. C. Yet, the form of the fable still has values today,     3     Rachel Carson says in “A Fable for Tomorrow.”

Carson uses a simple, direct style common to fable. In fact, her style and tone (口吻) are seemingly directed at children. “There was once a town in the heart of America,     4     all life seemed to enjoy peaceful existence with its surroundings,” her fable begins,     5     (borrow) some familiar words from many age-old fables. Behind the simple style, however, is a serious message     6     (intend) for everyone.

    7     (difference) from traditional fables, Carson’s story ends with an accusation instead of a moral. She warns of the environmental dangers facing society, and she teaches that people must take responsibility     8     saving their environment.

The themes of traditional fables often deal with simple truths about everyday life. However, Carson’s theme is a more weighty     9     (warn) about environmental destruction. Carson proves that a simple literal form that has been passed down through the ages can still     10     (employ) today to draw attention to important truths.

5 . Grizzly bears, which may grow to about 2.5 m long and weigh over 400 kg, occupy a conflicted corner of the American psyche — we revere (敬畏) them even as they give us frightening dreams. Ask the tourists from around the world that flood into Yellowstone National Park what they most hope to see, and their answer is often the same: a grizzly bear.

“Grizzly bears are re-occupying large areas of their former range,” says bear biologist Chris Servheen. As grizzly bears expand their range into places where they haven’t been seen in a century or more, they’re increasingly being sighted by humans.

The western half of the US was full of grizzlies when Europeans came, with a rough number of 50,000 or more living alongside Native Americans. By the early 1970s, after centuries of cruel and continuous hunting by settlers, 600 to 800 grizzlies remained on a mere 2 percent of their former range in the Northern Rockies. In 1975, grizzlies were listed under the Endangered Species Act.

Today, there are about 2,000 or more grizzly bears in the US. Their recovery has been so successful that the US Fish and Wildlife Service has twice attempted to delist grizzlies, which would loosen legal protections and allow them to be hunted. Both efforts were overturned due to lawsuits from conservation groups. For now, grizzlies remain listed.

Obviously, if precautions (预防) aren’t taken, grizzlies can become troublesome, sometimes killing farm animals or walking through yards in search of food. If people remove food and attractants from their yards and campsites, grizzlies will typically pass by without trouble. Putting electric fencing around chicken houses and other farm animal quarters is also highly effective at getting grizzlies away. “Our hope is to have a clean, attractant-free place where bears can pass through without learning bad habits,” says James Jonkel, longtime biologist who manages bears in and around Missoula.

9 . Imagine driving behind a huge truck shooting clouds of smoke into the air while your new fully electric vehicle cleans up its carbon emissions (排放). This dream may soon be a reality. A team of students in the Netherlands has created an electric car that not only doesn’t produce carbon dioxide when driving, but actually pulls it out of the air.

The two-seater sports car was designed and built in less than a year by a team of 32 students at Eindhoven University of Technology. Called “ZEM”, which stands for “zero emission mobility”, the car is equipped with special devices that remove carbon dioxide from the air as it drives. The team says if ZEM is driven about 32,000 kilometers, it can remove 2 kilograms of carbon dioxide from the air. That’s not a huge amount. The team calculates that 10 ZEM cars on the road for a year would remove as much carbon dioxide as a typical tree does during that time. However, they also point out that there are over a billion passenger cars in the world that could be using this technology. And if a billion cars were removing carbon dioxide instead of producing it, the result would be huge.

ZEM also has several other innovations that help to make it more capable of being sustained: the car’s frame and panels (面板) are 3D printed to reduce waste; it was built using recycled and recyclable materials; and it can be easily taken apart so that many of its parts can be reused. ZEM’s battery is also reusable, and has another handy feature: it can be charged with solar panels on the car’s roof—and can even be used to provide power to your house when the car isn’t on the road.

According to the statistics, transportation was responsible for over 20% of global carbon dioxide emissions in 2020—and of those emissions, cars were responsible for 41%. The Eindhoven team says its goal is to challenge the electric car industry: If 32 students can build a car like this in less than a year, then surely car manufacturers (生产商) are expected to adopt these innovations, too.

10 . Jumping rope is popular but we tend to ignore (忽视) its benefits.     1     A study found that college men who spent 10 minutes jumping rope daily for six weeks improved their cardiovascular (心血管的) fitness just as much as college men who spent thirty minutes jogging for the same time. Here are some benefits of jumping rope.

    2    

Since most of your major muscles are working when you jump rope, the exercise creates a lot of heat in the body. Your body needs to burn more fuel to produce this energy, so it burns lots of calories. It burns more calories than any other exercises, such as jogging, cycling and swimming.

Improves coordination (协调)

Jumping rope requires good coordination, especially as you advance to more skilled moves.     3     It improves coordination by requiring several body parts to communicate in order to complete one movement. The feet must jump in time with the wrists turning in order to create a continuous jumping motion.

Reduces injury risk

With your improved coordination from jumping rope, you’ll be less likely to get hurt either during exercise or in daily activities.     4     As a result, you are more agile (灵活的) and your body awareness is improved greatly. This guarantees fewer injuries.

Improves heart health

Since jumping rope gets your heart pumping, it’s great for your cardiovascular system and heart health. Jumping rope can increase your VO₂ Max (最大摄氧量), the measure of the maximum amount of oxygen a person can breathe during exercise. The higher someone’s VO₂ max, the more cardiovascular endurance (耐受力) they have.

Jumping rope gives us a full-body workout with just one piece of equipment and one move.     5     Jump to some music, or take your rope to a nearby park to enjoy the fun.