When a leafy plant is under attack ，it doesn't sit quietly. Back in 1983, two scientists, Jack Schultz and Ian Baldwin,reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be an alarm.What the plants pump through the air is a mixture of chemicals known as volatile organic compounds,VOCs for short.

Scientists have found that all kinds of plants give out VOCs when being attacked .It's a plant's way of crying out.But is anyone listening?Apparently.Because we can watch the neighbours react.

    Some plants pump out smelly chemicals to keep insects away.But others do double duty .They pump out perfumes designed to attract different insects who are natural enemies to the attackers. Once they arrive, the tables are turned. The attacker who was lunching now becomes lunch.

    In study after study,it appears that these chemical conversations help the neighbors .The damage is usually more serious on the first plant,but the neighbors ,relatively speaking ,stay safer because they heard the alarm and knew what to do.

Does this mean that plants talk to each other? Scientists don't know. Maybe the first plant just made a cry of pain or was sending a message to its own branches, and so, in effect, was talking to itself. Perhaps the neighbors just happened to “overhear” the cry. So information was exchanged, but it wasn't a true, intentional back and forth.

    Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate(亲密的) than the world we can see and hear. Our senses are weak. There's a whole lot going on.

    Long before they can actually speak, babies pay special attention to the speech they hear around them. Within the first month of their lives, babies' responses to the sound of the human voice will be different from their responses to other sorts of hearing stimulation. They will stop crying when they hear a person talking, but not if they hear a bell or the sound of a rattle. At first, the sounds that a baby notices might be only those words that receive the heaviest emphasis and that often occur at the ends of utterances(讲话，说话). By the time they are six or seven weeks old, babies can detect the difference between syllables pronounced with rising and falling tones. Very soon, these differences in adult stress and intonation can influence babies' emotional states and behavior. Long before they develop actual language comprehension, babies can sense when an adult is happy or angry, attempting to begin or end new behavior, and so on, merely on the basis of clues such as the rate, volume, and melody of adult speech.

    Adults make it as easy as they can for babies to pick up a language by exaggerating(夸张) such clues. One researcher observed babies and their mothers in six diverse cultures and found that, in all six languages, the mothers used simplified utterances and nonsense sounds, and transformed certain sounds into baby talk. Other researchers have noted that when mothers talk to babies who are only a few months old, they exaggerate the pitch, loudness, and intensity of their words. They also exaggerate their facial expressions, hold vowels(元音) longer, and emphasize certain words.

    More significant for language development than their response to general intonation is observation that tiny babies can make relatively fine distinctions between speech sounds. In other words, babies enter the world with the ability to make those precisely perceptual（知觉的，感性的） recognition that are necessary if they are to acquire listening language.

    Babies obviously obtain pleasure from sound input, too: even as young as nine months they will listen to songs or stories, although the words themselves are beyond their understanding. For babies, language is a sensory-motor delight rather than the route to boring meaning that it often is for adults.

    Last week, two companies, Kitty Hawk and Uber, announced their plans to bring flying cars to reality very soon.

    Imagine never having to worry about traffic, stop lights, or road construction. A flying car would get to a place much faster than one travelling by road. On the other hand, imagine having to avoid drones (无人驾驶飞机) and other flying cars. Also, what if your battery dies when you are in the air? And, how will you know where to land?

    Kitty Hawk is a start-up tech company supported by Google co-founder, Larry Page. According to the Kitty Hawk website, its car will be able to travel at speeds up to 40 kilometers an hour in the air. It says under US aviation law such a machine “does not require registration or a pilot's license and may be flown in uncongested (不拥挤的) areas for recreational purposes.” As of now, the car can only be flown over fresh water.

    Kitty Hawk is making a list of people interested in buying the flying car. They must pay a deposit of US$100. Those who get their names on the list early will receive US$2, 000 off the final cost of the car. However, Kitty Hawk has not yet announced the price. Kitty Hawk expects its first flying cars will go on sale by the end of this year.

    At a conference last week, Uber announced plans for flying taxis to begin carrying passengers. Unlike the Kitty Hawk company, Uber does not plan to build its flying cars. Instead, it will use the resources of partner companies.

    Like the Kitty Hawk car, Uber flying taxis will use electric power. Uber says its flying taxis could travel up to 241 kilometers an hour. The company said that could reduce the travel time between San Francisco and San Jose, California from two hours on the road to 15 minutes in the air.

    Riders could use the Uber app to book a flying taxi to take them to their destinations. The company has not yet said how costly air taxi travel would be compared to road taxi travel.

Craziest Food Festivals sounds like a joke topic, but once you start looking into it, you'll realize they're everywhere—the crazier, the better.

    ⒈Bibimbap Festival

    In the South Korean town of Jeonjuloves, their “mixed rice” dish is a hearty serve of rice topped with raw beef, a rainbow of vegetables, a raw egg and gochujang sauce (韩国的辣椒酱) so much. They take four days out of October to celebrate it.

    Like any festival there's music, entertainment and magic, but making it that little bit different is the bibimbap that's whipped (搅拌) up in a big bowl by dozens of chefs and served to over 400 people.

    ⒉Waikiki Spam Jam (怀基基午餐肉节)

    Who knew this canned meat had so much love? Well, it turns out that a can of Spam is the go-to item in Hawaii, along with a grass skirt and garland (花环). The people of Hawaii love Spam so much that they even spend a day in May serving out the best Spam, a type of cheap canned meat made mainly from pork.

    ⒊Bessieres Easter Egg Festival

    At Easter time, for those in the French town of Bessieres it's all about an egg far less sweet.

    Here they celebrate the holiday by getting dozens of chefs to make one large omelette (煎蛋卷) - 15,000 eggs strong - for the townsfolk (市民).

    ⒋Potato Days Festival

    This festival actually takes place in Barnesville, Minnesota(明尼苏达州), the US. Over the last Friday and Saturday in August the town celebrates its potato-growing skills by hosting potato picking and peeling contests, as well as a Miss Tater Tot pageant (盛典) for five-and six-year-old girls.

    These are instructions for making invisible ink using baking soda.

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