The term “to extend an olive（橄榄） branch” means to make an offer of peace or reconciliation(和好). This term has Biblical（圣经的）origins, coming from the section of the Old Testament that deals with the flood; the sign that the flood is over is an olive branch brought back to the ark(方舟) by a dove. Olive branches were also symbols of peace in Ancient Greece and Rome, and they continue to be used in various works of art that are meant to suggest peace.

    Some people have suggested that the olive was a very deliberate and well-considered choice as a metaphor(比喻）for peace, because olive trees famously take years to mature. War is typically very hard on the trees because people cannot take the time to nurture them and plant new ones. Therefore, the offer of an olive branch would suggest that someone is tired of war, whether it is an actual war or a falling out between friends.

    In Ancient Greek and Roman times, people would offer actual olive branches. In Rome, for example, defeated armies traditionally carried olive branches to indicate that they were giving in, and the Greeks used them into weddings and other ceremonies. In the modern era, the branch is usually metaphorical, rather than actual, not least because the plants can be a bit difficult to obtain.

    Many people agree that peace negotiations at all levels of society are a good idea. Between nations, obviously, it is important to extend an olive branch to ensure mutual safety and to help the world run more smoothly. This act can also be important on a personal level, as resolving conflict and learning to get along with others is viewed as an important life skill in many cultures.

    At some point in their lives, many people will be advised to extend an olive branch to settle a dispute or resolve an issue. Some people believe that it takes an immense amount of courage to take this action, as it often comes with an admission of wrongdoing and regret.

    Do you have trouble trying to create the next big idea? Sometimes the answer isn't to just force an idea out of your mind. Instead, you might want to try sitting back, relaxing and letting your mind wander. Yes, you heard that correctly. If you are in need of a new idea, try daydreaming.

    Researchers from the university of California, Santa Barbara, found an association between daydreaming and creative problem-solving. Their study includes having participants first do an "unusual-use task". They had to try to come up with as many different ways to use an object as they could.

    Then, the participants chose to do one of the following four things before doing the "unusual-use task" again: complete a difficult task; complete an easy task; take a 12-minute break; or skip the 12-minute break and move right on to the task exercise again.

    Surprisingly, the group that performed best was the one that completed the easy task. Many participants reported that they were daydreaming while performing the easy task. So the researchers believed that this daydreaming might have helped unlock their creativity.

    But how could daydreaming help the brain come up with creative ways? The answer is something known as "unconscious thought". Even when you are not actively working to solve a problem, it is still in the back of your mind. Your brain is still thinking about the problem, but in a much more subtle (不易察觉的) way.

    When you daydream, your mind is allowed to think in ways it normally would not. Because it is free of control, it can create completely new and out-of-the-box ideas.

    Great ideas never come easily, but that does not mean you always have to work hard to get them. Feel free to do what you want and let your mind wander.

    There's a new frontier (新领域) in 3D printing that's beginning to come into focus: food. Recent development has made possible machines that print, cook, and serve foods on a mass scale. And the industry isn't stopping there.

    Food production

    With a 3D printer, a cook can print complicated (复杂的) chocolate sculptures and beautiful pieces for decoration on a wedding cake. Not everybody can do that—it takes years of experience, but a printer makes it easy. A restaurant in Spain uses a Foodini to “re-create forms and pieces” of food that are “exactly the same,” freeing cooks to complete other tasks. In another restaurant, all of the dishes and desserts it serves are 3D-printed, rather than farm to table.

    Nutrition

    Future 3D food printers could make processed food healthier. Hod Lipson, a professor at Columbia University, said, “Food printing could allow consumers to print food to meet their own nutritional needs, like vitamins. So instead of eating a piece of yesterday's bread from the supermarket, you'd eat something baked just for you on demand.”

    Challenges

    Despite recent advancements in 3D food printing, the industry has many challenges to overcome. Currently, most ingredients must be changed to a paste (糊状物) before a printer can use them, and the printing process is quite time-consuming, because ingredients interact with each other in very complex ways. On top of that, most of the 3D food printers now are restricted to dry ingredients, because meat and milk products may easily go bad. Some experts are skeptical about 3D food printers, believing they are better suited for fast food restaurants than homes and high-end restaurants.

    Being an astronaut sounds cool, doesn't it? In space, they get to do some pretty amazing things, like floating (漂浮) in zero gravity(重力).

    However, there are also plenty of things that astronauts can't do because of their weightless environment(环境), and that's very sad. What's worse, they can't even let their sadness show -because it's impossible to cry in zero gravity.

    Of course, astronauts can still produce tears. But crying is much more difficult in space, reported The Atlantic in January. Without gravity；tears don't flow downward out of the eyes like they do here on Earth. This means that when you cry in space, your tears have nowhere to go — they just stick to your eyes.

    In May 2011, astronaut Andrew Feustel experienced this during one of his spacewalks. "Tears," he said, "don't fall off your eye...They just kind of stay there."

    Besides making your vision(视觉) unclear, this can also cause physical pain. Back on Earth, tears are supposed to bring comfort to the eyes. But that's not the case in space. The space environment dries out astronauts' eyes, and when tears suddenly wet the eyes, it can cause pain rather than comfort. "My right eye is painful like crazy." Feustel told his teammate during the walk.

    Since gravity doesn't work in space, astronauts need some extra help to get rid of the tears. Feustel chose to rub his eyes against his helmet to wipe the tears away. Another choice is to just wait — "When the tears get big enough they simply break free of the eye and float around," astronaut Ron Parise told The Atlantic.

    There are lots of small things — things like crying — that we are so used to on Earth, we usually take them for granted, until they become a problem in a totally different environment, like space. There, astronauts can't talk to each other directly. They also can't eat or drink in normal ways. They can't even burp (打嗝), because there is no gravity to hold the food down in their stomach. If they do burp, they just end up throwing up (呕吐) everything in their stomach, according to the UK National Space Center.

    Thus, perhaps it's only space explorers who can honestly say, "Gravity, you're the best."

    Foxes and farmers have never got on well. These small dog-like animals have long been accused (控告)of killing farm animals. They are officially considered as harmful and farmers try to keep their numbers down by shooting or poisoning them.

    Farmers can do call on the services of their local hunt to control the fox population. Hunting consists of hunting a fox across the countryside, with a group of specially trained dogs, followed by men and women riding horses. When the dogs eventually catch the fox, they kill it or a hunter shoots it.

    People who take part in hunting think of it as a sport; they wear a special uniform of red coats and white trousers, and follow strict codes of behavior. But owning a horse and hunting regularly is expensive, so most hunters are wealthy.

    It is estimated (估计) that up to 100,000 people watch or take part in fox hunting . But over the last couple of decades the number of people opposed to fox hunting, because they think it is cruel, has risen sharply. Noisy confrontations between hunters and saboteurs have become so common that they are almost as much a part of hunting as the hunting of foxes itself. But this year supporters of fox hunting face a much bigger threat to their sport. A Labour Party Member of the Parliament, Mike Foster, is trying to get Parliament to approve a new law which will make the hunting of wild animals with dogs illegal. If the law is passed, wild animals like foxes will be protected under the ban in Britain.

    The Children's Groundwater Festival, first organized by the Groundwater Foundation 19 years ago, is celebrated every year in Nebraska, a state of the central United States in the Great Plains. After organizing the festival for 16 years, the foundation passed the program on to the local community of Grand Island, Nebraska. The festival is an annual event for fourth and fifth graders of Nebraska. It is an interesting and energetic day filled with hands­on education. Water magic, folk singers and musicians, storytellers, and bird shows add to the happy atmosphere during the festival. There are also some educational activities:

    Gooey Garbage: Children build a landfill (废物填埋场) and learn how a properly­built landfill can protect groundwater.

    Water Races: Children learn about water pollution by racing a drop of water through a model.

    Well in a Cup: By building a small aquifer (蓄水层) in a cup, children learn about aquifers and drinking water wells.

    Taster's Choice: Children drink different types of water, from tap water to bottled water. Then they are taught about the treatment process of each type of water.

    There's No New Water: Students are taught to make a special glass container and learn about the water cycle.

    The Children's Groundwater Festival not only has a great influence on Nebraska's people. So far, similar festivals have been held in nearly 40 American states, Mexico City, several provinces in Canada, and New Delhi, India. People everywhere are realizing the importance of educating young people to learn and care about groundwater.

    For more information about this festival, remember to watch our program tomorrow evening. I'll be waiting for you.