A student is learning to speak British English. He wonders: Can I communicate with Americans? Can they understand me? Learners of English often ask: What are the differences between British and American English? How important are these differences?

    Certainly there are some differences between British and American English. There are a few differences in grammar. For example, speakers of British English say “in hospital” and “Have you a pen?” Americans say “in the hospital!” and “Do you have a pen?” Pronunciation is sometimes different. Americans usually sound theirs in words like “bird” and “hurt”. Speakers of British English do not sound theirs in these words. There are differences between British and American English in spelling and vocabulary. For example, “colour” and “honour” are British, “color” and honor” are American.

    These differences in grammar, pronunciation, spelling and vocabulary are not important. However, for the most part, British and American English are the same language.

    Christmas was near a season that we took seriously in our house. But a week or so before the 25th, my father would give each of his children $ 20. This was the 1970s, and $ 20 was quite a bit of money.

    But I saw it differently. My father trusted me to have the smart to spend money wisely. Even better, he gave me the means to get it. On a very basic level, my father was giving me a shopping spree (狂欢) every year.. But he was also giving me charge over my own fun, trusting my ability to manage money and making me feel like a grown-up. He didn't buy me Sherlock Holmes, but he gave me the means to walk into the bookstore and choose it for myself, so it felt like a gift from him.

    My mother had a gift for giving me what I needed, usually right at the moment I needed it most. This was when I was 25, I failed at being an adult on my very first try. I had quitted my previous job but had no new one. But when my mother paid me a visit, I put on a good show, telling her I had started my own company.

    My mother knew that I was trying hard and failing at that time. It wasn't until after she left that I noticed at the foot of my bed an envelope thick with cash. She knew how desperately I needed it. She knew that had she just shown up with groceries, or offered to pay my rent, she would have made me feel much worse. The cold, hard cash meant she was helping me. And, funnily enough, the distance with which she gave the gift felt like she was giving me space to fix my life and preserve my dignity. My mother and father both did the same thing. One was giving me the means to take my own decisions, and the other was giving me a second chance when those decisions had cost me dearly.

    Natural selection is the process by which one type of animal within a species thrives because of certain characteristics that make it more likely to live than others in its group. The history of the peppered moth（灰蛾）is an example of the natural selection process.

    In 19th century England, certain types of peppered moths were able to better blend（融合）into their surroundings. During that time period, great changes were happening in Great Britain. The Industrial Revolution was part of this change, and with it came air pollution. Natural selection often takes hundred or even thousands of years to occur. For the peppered moth, this process occurred comparatively quickly.

    At the beginning of the Industrial Age, most peppered moths in England were light-colored and covered with black markings, although a few moths had dark-colored wings. Because the light-colored moths blended into the light-colored bark on the trees, they could not be easily seen by birds that would eat them. As the air grew more polluted, however, tree trunks became covered with soot（烟煤）and became darker. The light-colored moths became easy for birds to see against the dark tree trunks. Since the dark-colored moths now had the advantage, their numbers grew. Within 50 years, the peppered moth went from being mostly light-colored to being mostly dark-colored.

    In the 20th century, the air cleared up, and the peppered moth population changed again. As tree trunks lighted due to less soot in the air, light-colored moths once again had an advantage. Their numbers increased as soot levels declined. Depending on their environment, the coloration of the moths helped them to be “naturally selected” to survive.

    Flat Holm, a small island in Britain's Bristol Channel, has no permanent residents and minimal infrastructure（设施）. The pretty land mass is now, however, becoming increasingly popular with tourists wishing to explore the rural landscape and view the island's seabird colonies.

    Though this is welcome news, meeting the island's growing energy needs without ruining its environment poses a challenge. Flat Holm team leader Natalie Taylor says, “As we promote the island more and we get more visitors here, there's going to be a lot more demand for electricity so it's really important that we've got a really high functioning system that can provide for those people. From an environmental point of view, we want to reduce the use of diesel（柴油）generators so that we can have as small ecological footprints as possible.”

    While the Cardiff Council, which oversees the island, considered traditional solar and hydroelectricity, it was reluctant to carry out either, due to their high cost and permanent nature. According to energy and sustainability manager Gareth Harcombe, the officials were seeking a portable option that could be moved if the site was needed for another purpose.

    Fortunately, the UK-based company Renovagen had the perfect solution. A small panel can provide 11kW of power within two minutes. A more extensive version, unrolled from a shipping container, can yield 300kW of electricity in less than an hour.

    The solar panel “carpets”, laid on the island in early October, are being used to provide electricity to its sole pub and lighthouse. The Cardiff Council also plans to use them to charge two Nissan e-NV200 electric vehicles in the future.

    In addition to providing power to remote islands like Flat Holm, Hingley hopes the Rapid Roll technology will be useful in areas affected by natural disasters. A good example is Puerto Rico, where most residents have been without electricity since Hurricane Maria destroyed the power lines in late September.

    I was driving down the road the other day, listening to sweet music coming out of my car radio. My heart felt peaceful, my mind was clear, and my soul was full of love. Even with all its problems: life seemed good. Then the music stopped and the news came on. There was talk of another famous millionaire in drug rehab (康复) after an incident with the police. There was news on the murder of a poor man whose life was supposed to be changed after winning the lottery. There was even a discussion on how much greed and excess (放肆) had damaged our world.

    Every story seemed to point once again to the old saying that money can't buy happiness. Hearing them made me think of a movie I saw many years ago on Mother Teresa's home for the dying in India. What struck me most when I watched it wasn't the unbearable poverty there. It wasn't the sickness and suffering that the people there were going through. It was rather the peaceful smiles of love, kindness, and happiness that they shared with the Sisters and with each other. These people had nothing. Many were struggling at the end of death. Yet, they knew the simple truth that so many of us here are still learning: Joy is Free.

    We can have joy and spread joy every day of our life here. Don't love or admire dollar signs and think that money will bring you happiness then. Joy can't be purchased. It can't be owned. It can only be chosen and then given freely to others. In the eyes of eternity (永恒), money is only worthless paper. The only thing that matters is the love within you and the love that you give to the world. Make that your legacy (遗产) and your life will forever be rich in joy.

A pair of researchers with Leibniz University of Hannover has demonstrated the means by which robots might be programmed to experience something similar to pain in animals. As part of their demonstration at last week's IEEE International Conference on Robotics and Automation held in Stockholm, Johannes Kuehn and Sami Haddaddin showed how pain might be used in robots, by interacting with a BioTac fingertip sensor on the end of a Kuka robotic arm that had been programmed to react differently to differing amounts of pain.

The idea of developing an artificial robot nervous system may seem contrary to all expectations, but Kuehn says doing so is important in the same way that it is good for humans to feel pain. "Pain is a system that protects us, "says Kuchn. "When we avoid the source of pain, it helps us not get hurt. "So when robots can feel and react to pain, they will become smart enough to avoid it. The more dangerous the robot registers the threat to be, the faster it will withdraw and avoid the source of danger. Additionally, Kuehn and Haddadin say humans working alongside robots that feel pain, especially those in heavy machinery, will be protected around them.

They have tested out some of their ideas using a robotic arm with a fingertip sensor that can detect pressure and temperature. It uses a robot-tissue patch(小片)modeled on human skin to decide how much pain should be felt and thus what action to take. For example, if the arm feels light pain, it slowly withdraws until the pain stops, and then returns to its original task; severe pain, meanwhile, causes the arm to go into a kind of lockdown mode until it can get help from a human operator.

Such robots are likely to raise a host of questions, of course, if they become more common —if a robot acts the same way a human does when touching a hot plate, are we to believe it is truly experiencing pain? Only time will tell of course, but one thing that is evident, Kuehn and Haddadin's work could lead to robots that are more human-like than ever.