1 . Why is pink or purple a color for girls and blue or brown for boys?

The answer depends largely on cultural values as well as personal experiences. To the Egyptians, green is a color that represents the hope and joy of spring, while for Muslims, it means heaven. Red is a symbol of good luck in many cultures. In China, children are given money in a red envelope to bring good fortune in the New Year. For many nations, blue is a symbol of protection and religious beliefs. Greek people often wear a blue necklace hoping to protect themselves against evils.

People’s choice of colors is also influenced by their bodies’ reactions toward them. Each color has its own function (功能). Red can cause a person’s blood pressure to rise and increase people’s appetites (食欲). Many decorators will include different shades of red in the restaurant. Similarly, many commercial websites will have a red “Buy Now” button because red is a color that easily catches a person’s eye.

Blue is a calming color. Unlike red, blue can cause people to lose appetite. So if you want to eat less, some people suggest that eating from blue plates can help. Green is said to be the most restful color. It has the ability to reduce pain and relax people both mentally and physically. People who work in green environment have been found to have fewer stomachaches.

The next time you are deciding on what to wear or what color to decorate your room, think about the color carefully.

2 . There was a time when a trip to the supermarket in the United States often ended with a seemingly simple question from the cashier, “Paper or plastic?” Well, which type of bag would you choose?

While both types of bags have some influence on the environment, it has long been supposed that paper bags are better. They are made from a renewable source, are broken down easily, burn without giving off thick smoke and can be recycled. However, the producing process behind paper bags uses more energy than that of plastic ones. How can this be true?

Studies show that paper bag production requires four times as much energy as plastic bag production. And the amount of water used to make them is twenty times larger. Besides, the influence on forests is very serious. It takes about fourteen million trees to produce ten billion paper bags, which happen to be the number of bags used in the United States yearly. In terms of recycling, the idea that paper bags are more environment-friendly than plastic ones can be quickly discarded. Research shows it requires about 98% less energy to recycle plastic than it does to recycle paper.

Even though paper bags might be more harmful than plastic ones, plastic still seems to be considered as the more harmful of the two by governments. In Ireland, for example, a tax has been introduced to discourage the use of plastic bags. People have to pay 22 cents for every plastic bag, and as a result, their use has dropped quickly.

There’s no doubt that it makes more sense to reuse these bags. However, we don’t seem to be doing that at present. That may be because they fall apart quickly. If so, cloth bags are a better choice, but still, their production also has a bad influence on the environment. So what to do? How should we answer the question of “Paper or plastic?” It seems that we first need to ask ourselves one more general question: “What can I do to help the environment?”

3 . Thanks to its cold environment, Antarctica (南极洲) remained largely untouched by humans for thousands of years. However, since the 1990s, the last true wilderness on the planet is becoming an increasingly popular destination for tourists. Now, a new study shows that the visitors may be bringing harmful bacteria (细菌) which could reduce the area’s native bird population.

Researchers believed that the Antarctic creatures were not affected by the danger due to the continent’s extreme weather. However, microbiologist Martà Cerdà-Cuéllar didn’t believe this was true. She and some colleagues decided to examine samples from Antarctic birds for evidence of human bacteria. To ensure the waste was not polluted, the scientists had to collect it from the birds themselves. This was no easy task. If they missed catching a skua at first go, the bird never came close again.

It took the scientists four years, from 2008 to 2011, to collect fecal (粪便) samples of 666 adult birds from 24 local species. The results of their study showed the presence of several types of human bacteria in the bird waste.

“While we should do as much as possible to reduce transmission (传播), it’s hard to believe that we can stop tourism and science at these sites, and so it is hard to believe that humans won’t continue to transmit pathogens (病原体),” said Kyle Elliott.

Experts, including González-Solís, believe the only way to prevent the destruction of the birds, is to introduce stricter regulations or, at least, obey the ones already in place. For example, while the Antarctica Treaty states clearly visitors carry their waste back home to protect the original environment, the regulation is rarely obeyed. Hopefully, officials will take steps to protect the easily injured birds as soon as possible.

5 . In 2002, Huang Hui, a researcher of the South China Sea Institute of Oceanology, went diving near Xisha. After that, she was left with memories of a beautiful experience with clear water and abundant colorful corals (珊瑚). However, much of the breathtaking scenery has disappeared due to climate change and human activities, which leads to the decline of the coral reef in the near shore waters. “We started to plant corals near the Xisha Islands in 2010, and restored more than 200, 000 square meters of coral reefs.” Huang said.

In 2004, when Huang was attending the 10th International Coral Reef Symposium, she found herself the only representative (代表) from the Chinese mainland. She said she felt sad but she made up her mind to strengthen communication with other countries to improve China’s level and status in coral research. She visited top coral researchers and set up long-term cooperation with some of them. By far, Huang has worked on coral research and protection for 22 years. Now, China is in a leading position in technology and coral planting.

Huang believes that people’s awareness of coral protection matters most to the sustainable (可持续的) development of the coral reefs. “I want to call on more people to love nature and ocean.” Huang said. Partly because of her efforts, Hainan Province released a law in 2017 forbidding reef trading and damaging.

“I hope that not only a coral island will be built but a sustainable development method will also be created,” said Huang. “ The ideal state is that the coral island should be able to support fishermen and protect the ecosystem.” she added.

6 . One of the talks from the TED stage in Long Beach, California, came from Richard Ture re, an inventor. He is a Maasai from Kenya. And he is very young.

Lions are the top tourist attraction to Kenya, especially in the Nairobi National Park, which is near where Richard lives. Lions are also considered critically endangered in Kenya. One of the main causes of their demise, “is that people kill them in retaliation (报复) for lions attacking their livestock (牲畜)”, says Paula Kahumbu, executive director of Wildlife Direct, a wildlife conservation organization in Africa. She has been studying the conflict between humans and lions, and her work led her to Richard. In one week, she monitored over 50 cases where lions attacked livestock.

One night Richard was walking around with a flashlight and discovered the lions were scared of a moving light. A light went on inside him and an idea was born. Three weeks later, Richard had invented a system of lights that flash around the cowshed (棚), which seemed like a human walking around with a flashlight. His system is made from broken flashlight parts and an indicator box from a motorcycle. “The only thing I bought was a solar board, which charges a battery that supplies power to the lights at night,” Richard says. He calls the system Lion Lights. “There have been a lot of efforts to try to protect the lions,” Kahumbu says. “It’s a crisis and everyone is looking for a solution. One idea was land leases (租赁), another was lion pro-offences (防护栅栏). And basically no one even knew that Richard had already come up with something that worked.”

His simple solution was so successful. He equipped the lights for his neighbors and for six other homes in his community. From there, the lights spread and are now being used all around Kenya.

To get to the TED stage, Richard traveled on an airplane for the first time in his life. He says he has a lot to tell his friends about when he goes back home, and what impressed him the most on his trip was something he saw at the Aquarium of the Pacific: “It was my first time seeing a shark. I’ve never seen a shark.”

9 . A city without cars would be very strange, right? But Venice is such a city.

Venice is in the north-east of Italy. It wasn't built on land, like Beijing or Shanghai, but on more than 110 islands. Sea water is everywhere around the city.

Even so, travel isn't difficult. The waterways have always been the best way to get around. There are 117 waterways and more than 400 bridges that can guide you where you want to go. People in Venice move from place to place by boat.

Water makes the city special, but it is also a big problem. Sometimes tourists will have such strange experiences. One moment they walk across the Rialto Bridge, and there's nothing special. But when they come back to the bridge an hour later, it's underwater and everyone is wearing rain shoes.

Once, people used too much underground water. This made the city get lower little by little. Now the city has gone down by 23 centimetres. Another problem is the rising sea water. The temperature has risen over the years. This has made the ice of the Arctic Ocean melt. Every year, high water hits the city in autumn and winter. When a lot of water comes, more than half of the city is underwater.

Scientists are trying different ways to stop the city from getting even lower. The Italian government has asked some of Italy's biggest companies to build the MOSE project, which was planned to be built under the sea water to stop the rising water. Anyway, this project is helping solve the problem.

10 . When I was six, Dad brought home a dog one day, who was called “Brownie”．My brothers and I all loved Brownie and did different things with her. One of us would walk her, another would feed her, and then there were baths, playing catch and many other games. Brownie, in return, loved each and every one of us. One thing that most touched my heart was that she would go to whoever was sick and just be with them. We always felt better when she was around.

One day, as I was getting her food, she chewed up (咬破) one of Dad's shoes, which had to be thrown away in the end. I knew Dad would be mad and I had to let her know what she did was wrong. When I looked at her and said, “Bad girl,” she looked down at the ground and then went and hid. I saw a tear in her eyes.

Brownie turned out to be more than just our family pet. She went everywhere with us. People would stop and ask if they could pet her. Of course she'd let anyone pet her. She was just the most lovable dog. There were many times when we'd be out walking and a small child would come over and pull on her hair. She never barked or tried to get away. Funny thing is she would smile. This frightened people because they thought she was showing her teeth. Far from the truth, she loved everyone.

Now many years have passed since Brownie died of old age. I still miss the days when she was with us.