6 . Zoos have been around for centuries — and they’ve changed a lot over the years. In the Middle Ages, wealthy people kept animals in their gardens. Public animal parks appeared in European cities in the late 1700s and early 1800s. The Philadelphia Zoo, the first in the United States, opened in 1874.

Until a few decades (十年) ago, most zoos were organized by creatures — monkeys in one area, cats in another, birds somewhere else, just like museum collections. In recent years, zoos have instead begun grouping animals that would normally interact (互相作用) in the wild. Moreover, instead of closing animals behind bars, designers are creating landscapes like the environments in which these creatures would naturally be found. Nearby signs provide information about the animals and their habitats in parts of the world where they normally live.

The Denver Zoo’s new Predator Ridge exhibit, for example, aims to teach visitors about Africa. Eight acres of land provide homes for 14 animal species, including lions, porcupines, cranes, and wild dogs. Plants from the region grow alongside African-like landform. Ten-foot-tall mounds (土墩) give lions a place from which to survey their surroundings, just as they would do in the wild.

Landscape design makes visitors to the Denver Zoo’s Predator Ridge exhibit feel like they’re really in Africa.

Animals in Predator Ridge can’t actually be mixed with one another, for safety reasons. But hidden deep channels and other smart features allow visitors to see all the animals at once. Different species can see each other too.

7 . School is still out for the summer, but at Eastern Senior High School, students are hard at work. In a garden bursting with vegetables and herbs, nearly a dozen teenagers are harvesting them for the weekend’s farmers market. They work Tuesday through Saturday with City Blossoms, a non-profit that brings community gardens to schools and other places where kids gather in urban(城市的) areas.

Roshawn Little, going into her junior year at Eastern, believes that working in the garden has taught her to try all sorts of new things — like eating different kinds of vegetables more often. And she has taken those healthy behaviors home with her and her family now buy more fruits and vegetables. ^“ We mainly live around liquor （酒）stores and snack stores. There aren’t that many grocery stores. They’re way out, and you have to drive so far ——a common problem in low-income urban areas .”

City Blossoms is one of many groups across the country teaming up with local communities to establish school gardens, like the one at Eastern. These gardens, advocates say, are really outdoor classrooms where kids learn valuable lessons — not just about nutrition, but also about science and math, even business skills. For example, the gardens can be used for math lessons — like calculating the area of a plant bed — or learning the science of how plants grow.

On a recent weekend at the Aya farmers market, the kids work at a table decorated with handmade signs that read “onions” and “garlic”, inviting people to try their herbed salt with bread. Working at the market helps them practice public speaking skills and business skills.

Nadine Joyner of a nutrition education company has a food table next to the kids’ at the market and often buys produce from them. She is constantly impressed by the kids’ knowledge of what they’re selling — they know how to grow it, how to prepare it, and how to cook it.

For a child fighting a serious     1    (ill), the days can be frightening, filled with hospitals and doctors. Make-A-Wish® Canada works     2    (give) each child the thing they want most.

“Wishes realized can give a child hope. It helps     3     (they) feel stronger,” says Megan Van Woezik, officer, at Make-A-Wish® Canada. The organization     4    (get) its start in Arizona in 1980. After 7-year-old Chris Greicius learned he had cancer, he worried that he wouldn’t realize his dream     5    becoming a police officer. On April 29, 1980, friends arranged for Chris to ride in a police helicopter.

After     6    (see) the happiness that the ride brought to Chris and his family, the friends decided to do the same for others and created the foundation. Three years later, a group of Canadians helped     7     young girl with leukemia (白血病) and started Make-A-Wish® Canada.

According to Van Woezik, wishes from kids     8    (usual) include: “to be”, “ to go”, “to have”, and “to meet”.

“ The influence of the wish is really     9    they get to feel special for something that isn’t about a medical condition,” Van Woezik says.

Young people often raise money for the foundation. “ Even if kids raise $100 in a year, or on their birthday, it' s really    10     (help),” Van Woezik says. “ It all adds up.”

The WWF is the world's     1    （large）organisation for nature conservation. It     2    （found）in the UK in 1961. Its aim was to protect the natural habitats of wild animals. The initials, WWF, stand for old World Wide Fund for Nature.    3    （original）the names was World Wildlife Fund. Today the organisation has     4    （branch）in 90 countries. It has thousands of volunteers and more than five million supporters who help by giving money.

In the 1980 s, the WWF became interested in all activities which have an effect on the environment, such as     5    （pollute）and the way we use energy. The WWF believe that our world has a future only if people learn       6    （conserve）nature and not to waste energy. As a result, it started working with governments to introduce environmental education into school.

The WWF has worked with the Chinese government since 1980,    7     Dr George Shaller arrived to work with Chinese scientist on the panda project. In 1995, the organisation set up     8     office in Beijing. Today     9     are more than thirty staff working on twenty projects all over the country. They include work in forests, energy, and in environmental education for China's primary and secondary schools as well as     10    （save）the panda, of cause.

10 . In 2012, Kim Stemple, a special-education teacher, found herself tied to an IV pole（输液架）in a Boston hospital being treated for one of several diseases she had. Before she got too sick to exercise, Stemple had been a marathon runner. She was naturally getting very depressed. And then a racing partner who had just finished a half marathon in Las Vegas gave her a medal and hoped the keepsake would act as a kind of pick-me-up. It worked like a charm.

After Stemple hung the medal from her hospital IV pole, other patients said they wanted medals too. That got Stemple thinking. “A medal is a simple way to give a positive message,” she told pilotonline.com. And so was born her charity, We Finish Together, which collects medals from strangers—runners, dancers, swimmers, singers, and even spelling bee winners—and donates them to all sorts of people in need.

People who receive the medals have included hospital patients, residents of homeless shelters, and veterans. Part of the process involves the donor writing a personalized note on the ribbon（授带）, “This gives them a connection to someone,” says Stemple. “If they receive a medal, they know someone cares.”

Can a simple medal really make a difference? Yes, says Joan Musarra, who suffers from a terrible disease. “I opened my package containing my new medal and the note of positive, warm thoughts. I was deeply touched,” she wrote to Stemple. “At that moment, I was sitting on my couch breathing through an oxygen cannula（插管）because my lungs had worsened so badly. It means so much to me to feel that I am not alone.”