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.

    The Americans believe that anybody can become president of the United States. In a recent Hollywood comedy, that is exactly what happens.

    Dave Kovic, played by Kevin Kline, is a kind-hearted man who runs a business that finds people jobs. He leads a typical American way of life, except for one thing－he looks exactly like the president, Bill Mitchell. In fact, the only thing that makes him different from the nation's leader is that he is very nice!

    The president has started using look-alikes during some public appearances. Dave is offered a chance to “serve his country” by becoming one. However, things go wrong. The president becomes very ill and Dave ends up acting as the president forever.

    Director Ivan Reitman, who made the popular and successful comedies like Twins, Ghostbusters and Legal Eagles, could have gone for easy laughs by making fun of the American government. Instead, Dave is an attractive comedy about an ordinary man in extraordinary situations. Kevin Kline gives a double performance as Dave and the president, and Sigourney Weaver is at her best as his First Lady. The love story that develops between her role and Dave is a real classic.

    The film is 100% American. However, if you've ever felt that anybody could do a better job running the country than the people in power, then you'll enjoy Dave!

    My family was gathered for a barbecue when the discussion arose about a celebrity who earned a large amount of money. The major criteria for receiving millions of dollars seem to be determined by how much the audience will pay to watch the performer achieve.

    The discussion led to a sudden self-questioning. Why did I choose teaching for a career? I half-listened to their conversation as I pondered the answer.

    I remembered my three children watching me spend nights planning for my class. I remembered how they intently listened to my frustrations concerning materials, procedures and the amount of responsibility that seemed to endlessly be thrust into the laps of classroom teachers. I remembered when it came time for each of my own children to choose a profession. How I waited to hear if any had plans to follow Mom into teaching. Long considerations held no mention of anyone becoming a teacher.

    Dessert was being served, and everyone was still involved in the discussion of the enormous salary of one individual, when the phone rang. My husband handed the phone to me.

"Hello, this is Bonnie Block," I said.

"Is this the Bonnie Block who used to teach kindergarten?"

    A nervous sensation swelled in me, and my mind raced with memories of those days long ago.

"Yes!" I exclaimed with a lump in my throat. It seemed like forever as I waited anxiously to hear what the caller would say next.

"I am Danielle—Danielle Russ. I was in your kindergarten class."

    Tears of surprise and joy rolled down my flushed cheeks.

"Yes," I uttered softly as I remembered that darling, wonderful child.

"Well, I am graduating from high school this year, and I have been trying to find you. I wanted you to know what a difference you made in my life."

She proceeded to give details. My influence on her wasn't limited to kindergarten but remained a strong motivating force when she needed a coach to help her meet a challenge. "I pictured you praising and encouraging me all the way."

    Why choose teaching?

    The pay is great!

Disney has picked Chinese actor Liu Yifei to play Mulan in an upcoming film, following accusations against Hollywood of ‘whitewashing'.

    Several Hollywood films have faced criticism in recent months for featuring white actors in Asian roles. Recent films accused of whitewashing include the Hollywood remake of Japanese anime Ghost in the Shell, which had Scarlett Johansson in the main role which was originally Japanese, and Chinese epic The Great Wall which starred Matt Damon as its lead character. Earlier this year, British actor Ed Skrein who was cast as an Asian character in the upcoming Hellboy remake pulled out of the film so that the role could be “cast appropriately”. It then went to Korean-American actor Daniel Dae Kim.

    The live-action adaptation of the 1998 cartoon movie will tell the tale of the well-known Chinese heroine Hua Mulan. Mulan pretended to be a man to fight in the army to spare her weak father from being forced into the army.

    The film has been under careful examination since it was announced that Disney intended to remake Mulan. An online campaign calling for an Asian actress in the role attracted more than 100,000 signatures before it was shut on Thursday.

    Liu, nicknamed “Fairy Sister” for her delicate looks and previous roles in fantasy dramas, is well-known as an actress, model and singer in China. The 30-year-old is said to be fluent in English, having grown up partly in New York. The Hollywood Reporter said she was picked out of nearly 1,000 candidates for the film.

Disney's announcement on its blog about Liu's casting was met with delight on Twitter as well as on Sina Weibo, China's microblogging network. Many online celebrated it as a win for diversity in Disney films. Chinese-American actress Ming-Na Wen, who voiced Mulan in the original animated movie, also gave her stamp of approval. Chinese netizens congratulated Liu, with many praising Disney's choice. One commenter said, “Needs to know martial arts, can also speak English, has star quality - it definitely should be Liu Yifei.”

    The young boy saw me, or rather, he saw the car and quickly ran up to me, eager to sell his bunches (串) of bananas and bags of peanuts. Though he appeared to be about twelve, he seemed to have already known the bitterness of life. "Banana 300 naira. Peanuts 200 naira"

    He said in a low voice. I bargained him down to 200 total for the fruit and nuts. When he agreed, I handed him a 500 naira bill He didn't have change, so I told him not to worry.

    He said thanks and smiled a row of perfect teeth.

    When, two weeks later, I saw the boy again, I was more aware of my position in a society where it's not that uncommon to see a little boy who should be in school standing on the corner selling fruit in the burning sun. My parents had raised me to be aware of the advantage we had been afforded and the responsibility it brought to us.

    I pulled over and rolled down my window. He had a bunch of bananas and a bag of peanuts ready. I waved them away. "What's up?" I asked him. "I… I don't have money to buy books for school." I reached into my pocket and handed him two fresh 500 naira bills.

    "Will this help?" I asked. He looked around nervously before taking the money. One thousand naira was a lot of money to someone whose family probably made about 5,000 naira or less each year. "Thank you, sir," he said. 'Thank you very much."

    When driving home, I wondered if my little friend actually used the money for school-books. What if he's a cheat? And then I wondered why I did it. Did I do it to make myself feel better? Was I using him? Later, I realized that I didn't know his name or the least bit about him, nor did I think to ask.

    Over the next six months, I was busy working in a news agency in northern Nigeria. Sometime after I returned, I went out for a drive. When I was about to pull over, the boy suddenly appeared by my window with a big smile ready on his face

    "Oh, gosh! Long time."

    "Are you in school now?" I asked.

    He nodded.

    "That's good," I said. A silence fell as we looked at each other, and then I realized what he wanted. "Here," I held out a 500 naira bill. "Take this." He shook his head and stepped back as if hurt. "What's wrong?" I asked. "It's a gift"

    He shook his head again and brought his hand from behind his back. His face shone with sweat (汗水). He dropped a bunch of bananas and a bag of peanuts in the front seat before he said, "I've been waiting to give these to you."

Earthquake rescue robots have experienced their final tests in Beijing.Their designers say with these robots，rescuers will be able to have more time to save more lives during an earthquake.

This robot，looking like a helicopter，is called the detector bot.It's about 4 meters long，and it took about 4 years to develop the model.Its main functions are to collect information from the air，and send goods of up to 30 kilos to people trapped by an earthquake.

This robot has a high－definition 360－degree panoramic(全景的) camera.It can work day and night and will also be able to send the latest pictures from the quake area.

Dr.Qi Juntong，from the Chinese Academy of Science，said，"The most important feature of this robot is that it doesn't need a distant control.We just set the destination(目的地) information on it，and then it takes off，and lands by itself.It flies as high as 3，000 meters，and as fast as 100 kilometers per hour."

This robot has a different function—it can change as the environment changes.Its main job is to search for any signs of life in places where human rescuers are unable to go.

As well as a detector(探测器) that finds victims and detects poisonous gas，a camera is placed in the 40－centimeter－long robot，which can work in the dark.

Another use for the rescuers is the supply bot.With its 10－meter－long pipe，people who are trapped in the ruins，will be able to get supplies including oxygen and liquids.

Experts have said that the robots will enter production，and serve as part of the national earthquake rescue team as soon as next year.