A rainforest is an area covered by tall trees with the total high rainfall spreading quite equally through the year and the temperature rarely dipping below 16℃. Rainforests have a great effect on the world environment because they can take in heat from the sun and adjust the climate. Without the forest cover，these areas would reflect more heat into the atmosphere, warming the rest of the world. Losing the rainforests may also influence wind and rainfall patterns，potentially causing certain natural disasters all over the world.

    In the past hundred years，humans have begun destroying rainforests in search of three major resources（资源）: land for crops，wood for paper and other products，land for raising farm animals. This action affects the environment as a whole. For example，a lot of carbon dioxide（二氧化碳）in the air comes from burning the rainforests. People obviously have a need for the resources we gain from cutting trees but we will suffer much more than we will benefit.

    There are two main reasons for this. Firstly，when people cut down trees，generally they can only use the land for a year or two. Secondly，cutting large sections of rainforests may provide a good supply of wood right now，but in the long run it actually reduces the world's wood supply.

    Rainforests are often called the world's drug store. More than 25％ of the medicines we use today come from plants in rainforests. However，fewer than 1％of rainforest plants have been examined for their medical value. It is extremely likely that our best chance to cure diseases lies somewhere in the world's shrinking (萎缩的) rainforests.

    Students taking Georgia Tech's online Knowledge-Based Artificial Intelligence course received some surprising news. Jill Watson one of the nine teaching assistants(TAs) that had helped them finish the challenging course for the past five months was not a ‘‘she'' but an “it”—an intelligent robot!

    Watson is the brainchild of Ashok Goel, who teaches the popular online course. The Professor-of Computer and Cognitive Science in the School of Interactive Computing came up with the idea as a way to deal with a number of questions posed by students in the online forums(论坛). According to Goel, every time the course is offered, the 300 or so students that enroll post over 10,000 questions which are often repetitive. This led Goel to wonder if a smart robot would handle the questions which require standard responses.

    Having worked' with IBM's Watson technology platform in the, the professor knew it would be ideal for his artificial TA: Jill Watson. The artificial intelligence system that uses natural language processing and machine learning to analyze large amounts of data has even been cleverer than human competitors on the television show. It would therefore easily be able to handle routine questions that required little “thinking”.

    The professor and his team of graduate students began by populating Jill's memory with 40,000 questions and answers from past terms. Then came the testing stage. At first, Jill was not very good and often gave strange answers. It often got stuck on certain keywords. By the end of the semester, Jill had attained enough knowledge and skills to participate in forums without any management from Goel, or the other assistants.

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    Who is smarter? A human being or artificial intelligence?

The question swept the world last week when a Google-developed program called AlphaGo defeated the world top player, South Korean Lee Se-dol, 4-1.

    So, what comes next?

    Some people have been arguing that artificial intelligence, or AI in short, will be a bad thing for humans. In an interview with the BBC in 2014, UK scientist Stephen Hawking warned that “The development of full artificial intelligence could mean the end of the human race.”

    So are we really about to live in the world shown in the Terminator movies?

    “Not quite,” answered The Economist. After all, it's not hard to get a computer program to remember and produce facts. What is hard is getting computers to use their knowledge in everyday situations.

    “We think that, for the human being, things like sight and balance(视觉平衡), are natural and ordinary in our life.” Thomas Edison, founder of Motion Figures, a company that is bringing AI to boys, told the newspaper. “But for a robot, to walk up and down just like human beings requires various decisions to be made every second, and it's really difficult to do.”

    As The Economist put it, “We have a long way to go before AI can truly begin to be similar to the human brain, even though the technology can be great.”

    Meanwhile, John Mark off of The New York Times said that researchers should build artificial intelligence to make people more effective.

    “Our fate is in our own hands,” he wrote. “Since technology depends on the values of its creators, we can make human choices that use technology to improve the world.”

    At the age of seven, while his friends were spending their allowances on candy and toys, Jose Adolfo Quisocola, Peru, came up with the creative idea of an eco­bank which allows kids of all ages to become economically independent and financially wise while helping the environment.

    Established in 2012, The Bartselana Student Bank is the world's first cooperative bank for kids. Whoever wants to join has to bring in at least 5 kilograms (11 pounds) of solid waste (paper or plastic) and establish a savings goal. Once accepted, all bank "partners" are required to deposit at least one additional kilogram (2* 2 pounds) of recydables on a monthly basis and obey other requirements, such as attending financial education and environmental management workshops. The waste accumulated is sold to local recycling companies, who, thanks to some clever negotiation by Jose, pay a higher­than­market rate for everything brought in by Bartselana Student Bank members. The funds received are placed in the individual's account where they collect until his/her savings goal is reached. The account holder can then withdraw his/her money, or choose to leave it and continue to grow for a bigger target.

    "At the beginning, my teachers thought I was crazy or that a child could not undertake this type of project," Jose recalls. "They did not understand that we are not the future of the country but its present. Luckily, I had the support of the school principal and an assistant in my classroom."

    The youngster's persistence paid off. Today, the eco­bank, which now has the support of several local institutions, has ten educational centers and begins accepting applications from kids all across Peru. On November 20, 2018, the young boy was awarded the famous Children's Climate Prize (CCP). "Jose's eco­bank is a brilliant way of linking economy and climate impact, both in thought and practice. The potential impact is amazing", a judge said.

    Hopefully, Jose's success will inspire more kids and adults to come up with new ideas that create value while helping the environment. As the boy says, "Together we can change the world, we just need an opportunity."

    A dog spent the last four years of his life waiting a crossroad in the Thai city of Khon Kaen as if waiting for someone. People originally thought the dog had been abandoned, but then realized that he looked healthy, so people asked around about him. It turned out that the dog had indeed been spending most of his time around that crossroad, but a woman had been coming round regularly to bring him food and water.

    One day, while photographing the dog everyone called Leo, a reporter met the woman who had been taking care of him. She had come to drop off some food. After learning the story about the dog and the woman, the reporter decided to share the story on social media. The post soon went viral and the photos of Leo got shared hundreds of times. And the photos reached the eyes of Leo's former old owner.

    Nang Noi Sittisarn, a 64-year-old woman from Thailand's Roi Et Province, almost had a heart attack when her daughter showed her a photo of the beloved dog named BonBon she had lost during a car trip. When she learned that he had been waiting for her in the same spot for the last four years，her heart melted(融化).

    Auntie Noi told her daughter to drive her to where the dog was waiting. When she got there and called his name. BonBon, the poor dog started wiggling(扭动)his tail and came to her, but when she tried to take him home with her, he was unwilling to follow. She didn't want to force the dog to come with her, so she agreed to leave him with his new master. However, she and her daughter will come to visit him regularly.