I'm part of the Roots & Shoots program founded by Dr. Jane Goodall. The program is intended to make and promote positive changes in the world. As Dr. Goodall says, "What you do makes a difference, and you have to decide what kind of difference you want to make."

    In Bulgaria, where I live, homeless dogs are everywhere. Many people here turn a blind eye to them. But I cannot ignore the life of a street dog whenever I see one wandering in the street, looking for something to eat. That's why I'm no longer a food waster. When I see wasted food, I always think of a hungry dog climbing to garbage bins, searching for food that people have thrown there. When eating in a restaurant, I'm not afraid to take leftover food to feed stray cats or dogs.

    A week ago, I saw a homeless dog around the garbage bins. Immediately I knelt down, spoke to her softly and ran my hands over her. I could see that she had had puppies. I couldn't imagine how she could have been able to care for them. Hours earlier, I'd bagged up a plate of leftover fish. As I unwrapped it, she wagged her tail and sniffed at it. She ate all the fish in no time.

    It's sad, isn't it? I can't understand why many of us waste so much and think little of it. These homeless animals have taught me that food is precious. Even when I don't have leftovers with me, I'll take the time to get something from the grocery store to feed them.

I know my power is small, so I hope that next time you see wasted food, do turn it into worthy food. You have the power to save a life!

    While Jennifer was at home taking an online exam for her business law class, a monitor（监控器）a few hundred miles away was watching her every move.

    Using a web camera equipped in Jennifer's Los Angeles apartment, the monitor in Phoenix tracked how frequently her eyes moved from the computer screen and listened for the secret sounds of a possible helper in the room. Her Internet access was locked — remotely — to prevent Internet searches, and her typing style was analyzed to make sure she was who she said she was: Did she enter her student number at the same speed as she had in the past? Or was she slowing down?

    In the battle against cheating, this is the cutting edge and a key to encouraging honesty in the booming field of online education. The technology gives trust to the entire system, to the institution and to online education in general. Only with solid measures against cheating, experts say, can Internet universities show that their exams and diplomas are valid — that students haven't just searched the Internet to get the right answers.

    Although online classes have existed for more than a decade, the concern over cheating has become sharper in the last year with the growth of “open online courses”. Private colleges, public universities and corporations are jumping into the online education field, spending millions of dollars to attract potential students, while also taking steps to help guarantee honesty at a distance.

    Aside from the web cameras, a number of other high-tech methods are becoming increasingly popular. Among them are programs that check students' identities using personal information, such as the telephone number they once used.

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    There is an old style out there of young girls talking endlessly on the phone with one another. It's an idea that is far from untrue in many families. I remember being a twelve-year-old and spending some quality time on the phone with my girl-friends, even though we'd seen each other at school. I didn't really have anything to talk about, I guess, but I think I was just happy to have someone else to talk to and that someone wanted to talk to me.

    We call this phenomenon (现象) of girls going on forever over the regular phone “girl talk”. And these days, girl talk has spread far beyond the old phone-teens communicate with each other pretty much nonstop through cell phone, texting，online chat. Is girl talk a good thing? According to experts, it can be-in limited quantities.

    Girl talk has its place. But too much of it, especially the kind during which problems are talked about endlessly can be not such a good thing. Psychologists (心理学家) think that too much of that kind of talking can lead to emotional problems such as depression (沮丧) and anxiety. Girls, much more so than boys, will always think of a problem and get worried, making the problem worse other than solving it. The best way is to try to guide the conversation toward something positive, or to do something about the problem rather than sit around and chat about it endlessly.

    When I was a boy there were no smart phones, and our television only got one channel clearly. Still, I never felt bored. The fields, hills and woodlands around my home were the perfect playground whose adventures were only limited by my imagination. I can remember once hiking to a nearby lake and walking slowly around it. At the back of it I was amazed to find an old dirt road that I had never seen before. It was full of muddy tyre tracks and deep woods on both sides, but exploring it still seemed like a fine adventure.

    I walked on and on for what seemed like hours. I was sure my guardian angel was whispering in my ear “turn around and head back home”, but I was stubborn and walked on. There was still neither a car nor a house in sight. I noticed that the sun was starting to go down and I grew scared. I didn't want to end up trapped on this road, and I was worried that it would be dark before I could make my way back to the lake again.

    I continued to walk on with something growing inside of me. My heart was pounding and my legs were aching. I was almost in tears when I saw something in the distance. It was a house that I recognized. I jumped up and down and laughed out loud. It was still over a mile away, but my legs felt like feathers and I hurried back to my house in no time. I walked in with a big smile on my face just in time for dinner. Then I ended my adventure with a good night's sleep.

    I often thought of that experience recently. Actually, in our life, all roads, no matter how they twist and turn, can lead us home again. They can lead us to our homes here on the earth. They can lead us to our homes in our hearts. May you always walk your path with love! May you always help your fellow travelers along the way! And may your roads always lead you home again!

    If you live in Shanghai, you might have to take a "lesson" in sorting garbage, as the city recently introduced new garbage-sorting regulations. It's now required that people should sort garbage into four categories, namely recyclable, harmful, dry and wet waste. However, if people fail to sort their garbage properly, they can be fined up to 200 yuan. More cities are introducing similar regulations, following the practice in Shanghai. By the end of 2020, garbage-sorting systems will have been built in 46 major Chinese cities, including Beijing and Shenzhen, reported People's Daily.

    According to a study by the Policy Research Center for Environment and Economy, under the Ministry of Ecology and Environment, over 90 percent of the public believe that garbage sorting is important for the protection of the environment. However, garbage sorting is still a big problem in China. Only 30 percent of participants said they think they are adequately sorting their trash, the study noted.

    According to Xinhua News Agency, it's partly because many people lack the willingness to sort their own waste. In the past, some previous garbage regulations didn't give clear fines for people who failed to sort garbage. "It's a must to have a legal guarantee to promote garbage sorting." Liu Jianguo, a professor from Tsinghua University, told China Daily. He also added "the importance of the new regulations in Shanghai is to change the past voluntary action into compulsory action for everyone"

    Aside from China, many other foreign countries have also introduced garbage-sorting regulations. In Japan, waste sorting has become a basic survival skill, reported Xinhua. There is a fixed time for disposal of each kind of garbage and littering can result in high fines and even jail time. In Germany too, people are asked to sort waste into specific categories, reported HuffPost. For example, in Berlin, people have yellow bins for plastic and metals and blue bins for paper and cardboard.