Dolphins(海豚) live in a dark underwater world. It's often impossible to see each other or anything else around them, so sound plays an important role in their survival. To communicate with each other, dolphins produce all kinds of sounds.

    Only other dolphins understand what the sounds mean. Scientists haven't uncovered their secret communication, except for one kind of whistle. It might last less than a second, but this whistle is a big deal. Why? Because these whistles are actually names of dolphins - and every dolphin has one. Scientists call these sounds a “signature whistle.” When other dolphins hear the whistle, they know which dolphin is calling.

    Dolphins often hunt by themselves but still need to stay connected to the group. Since they can't always see each other, dolphins use their signature whistles to check in with other dolphins hundreds of yards away. “In coastal areas, dolphins exchange whistles even when they're a third of a mile apart,” says Greg Campbell, who studies animals. That means dolphins shout out to group members that might be nearly five football fields away.

    What's amazing is who names the baby dolphin. Not the mother. Not an auntie dolphin or another group member. Scientists believe the baby dolphin itself comes up with the signature whistle. Like human babies, a baby dolphin plays with sounds throughout its first year. While testing its sound skills, a baby dolphin is doing something amazing. It's creating or figuring out its signature whistle. How or why it chooses its signature whistle is not clear. Studies show that most of the time the signature whistle is nothing like its mother's or group members' whistles.

    When the baby dolphin is about a year old, its signature whistle is set. It repeats it often so the other dolphins learn to recognize it.

    Deciphering(破译) dolphin names is just the beginning of figuring out what dolphins communicate about. Do they chat about sharks? Discuss the tides? Maybe they even have a name for people. Someday scientists are to decipher the rest of dolphins' communication.

    On Monday, the Centers for Disease Control and Prevention predicted that 42% of Americans could be overweight by 2030. Our expanding waistlines lead to not only a medical problem, but according to a recent article In The New York Times, it could also endanger personal safety in some situations—in an airplane crash, for example.

    The New York Times' Christen Negroni reports that engineers and scientists are questioning whether airplane seats are adequately constructed to protect overweight travelers. Government standards for airplane seat strength（强度）— first set moe than 60 years ago — require that the seats be made for a passenger weighing 170 pounds (77kg). Today, the average American man weighs nearly 194 pounds (88kg) and the average woman 165 pounds (75kg). Negroni reports:

    “If a heavier person completely fills seat, the seat is not likely to behave as intended during a crash,” said Robert Salazar, the leading scientist at the Center for Applied Biomechanics at the University of Virginia. “The energy absorption that is built into the aircraft seat is likely to be overpowered and the passengers will not be protected properly.”

    “Nor would the injury be limited to that passenger only,” Dr. Salzar said. “If a seat or a seat belt fails,” he said, “those people who are seated nearby could be endangered from 'the uncontrolled movements of the passenger'.”

    Most complaints about airplane seats focus on their lack of comfort and high ticket price, and whether overweight passengers should be made to buy two seats. But The New York Times' article brings up another reason to feel anxious about flying. Investigators of the issue got in touch with the airplane seat and seat belt makers, but they refused to comment on the problem. Experts agreed that crash testing should be done with overweight dummies （人体模型）. Both airplane seats and seat belts should be tested, they said.

    Fortunately, however, according to Nora Marshall, a senior adviser at the National Transportation Safety Board, the board's investigators have never seen an accident involving a commercial plane in which the weight of a passenger was a problem.

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    The universe looks like a pretty quiet place to live. But the universe is filled with dangerous things, all struggling to be the one to wipe us off the planet. Happily for us, they're all pretty unlikely, but if you wait long enough, one of them is certain to get us. But which one?

1). Death by Asteroid (小行星)

    Of all the ways we might meet our untimely death, getting wiped out by an asteroid is the most likely. Why? Because we sit in a universal shooting gallery, with 100 tons of material hitting us every day. The problem, though, occurs every few centuries when something big this way comes. If you could ask a dinosaur, I'd imagine they would tell you to take this seriously.

2). Death by Exploding Star

    When a huge star ends its life, it does so with a bang, which sends death spreading across space in the form of high-energy radiation. Many studies show that the bang would have to be closer than about 75 light years to do us any harm. The good news: no stars so close are able to do the deed.

3). Death by Dying Sun

    The sun is important to us; without it, we'd freeze. But the sun is also middle-aged, already halfway to running out of fuel, expanding into a red giant, and cooking us to a fine crisp. Even long before then, it'll warm up enough to raise our average temperature and cause a runaway greenhouse effect, boiling our oceans. Happily, that's a long time from now.

4). Death by Black Hole

    Black holes are misunderstood. They don't wander the galaxy looking for tasty snacks in the form of planets and stars; they turn around the Milky Way just like the hundreds of billions of other stars do. But it's possible that one could wander too close to us. If it did, planetary paths would be disturbed, causing the Earth to drop into the sun or be thrown out into deep space.

    Given that it could be trillions of years or more before even that happens, we don't have to worry too much about black holes.

    My advice? Go outside, look up, enjoy the sun, the moon, and the stars. They may be there forever as far as any one of us is concerned...and forever is a long, long time.

    Chinese writers seldom win a big prize in the world. One of those prizes is the Hans Christian Andersen Prize, the highest honor in the world that can be given to an author and an illustrator of children's books. No Chinese writer had ever won it, until April 4, 2016, when 62-year-old Cao Wenxuan received the prize. Cao received the honor at the Bologna Children's Book Fair in Italy.

    Patricia Aldana praised Cao's “deeply humanistic” books. These novels admit that life can be sad for children.

    Instilling children with good virtues for the sake of humankind is something that Cao stresses. He said, “It's time for us to alter our understanding of reading. Books should bring not only joy to young readers, but also have their ideas about life.”

    That feature of his works has touched many adults too. “The common choice of the judges, Cao writes beautifully about the lives of children facing great challenges,” said Aldana.

    After his success, Cao praised good translation for bringing attention to his work. Chinese children's literature could get high honor in the world if it were correctly translated in a style that could be easily understood, he said.

    Other writers, including Jin Bo, have also blamed poor translation as the reason why Chinese literature fails to get honor in the world. Jin was named for the Hans Christian Andersen Prize in 1992, but at that time, he had to translate, in a hurry, several paragraphs from his book to give to the judges. "On one hand, the jury has little knowledge of Chinese authors. On the other hand, it is we ourselves who didn't introduce our work and promote (促进) ourselves enough," he said in a class in 2013.

    The town of Green Bank, West Virginia, is the site of the largest radio telescope in the world, so Internet connections and anything else that can create electromagnetic(电磁的) waves, such as smart phones and microwave ovens, are banned.

    Green Bank is frozen in time, somewhere in the 1950s, because there's a 33,000-square-kilometer zone of silence due to the telescope. Cell phone towers are forbidden.

    The closer you get to the telescope, the greater the restrictions. There's a 16-kilometer radius(半径) around the observatory where radio-controlled items, even toys, cannot be used.

    Telescope employees even work in a special room that blocks electromagnetic waves from leaving it. “Here imagine a submarine(潜艇), water cannot get inside, and so this room is an electric submarine. No electromagnetic waves can get into this room, just as you can't go beyond it,” Michael Holstein, an observatory officer, said.

    The size of a football field, the telescope is so sensitive that it could pick up signals sent from an alien world. And scientists can't wait for that to happen.

    “All the signals that we now receive with the help of telescopes are signals that come from cosmic objects — stars, galaxies. We have not yet received anything from intelligent civilizations,” scientist Richard Lynch said.

    Local people respect the work of the scientists. “Yes, we are different. Many would say that we live the old-fashioned way, in the past. But for us, it's just the way of life that we have always lived,” Sherry said.

    “When we want to meet friends, we just call each other on a wire phone. And instead of sitting in front of your screen, we talk, we go fishing, to the mountains,” resident Sherry said.

    For the latest news, residents read the weekly local newspaper. When she's looking for a phone number, Sherry reaches for the phone book.

    And instead of Facebook, Sherry enjoys daily conversations with her customers. In this town, everyone knows each other and communication is face to face.

    When my sister Mertie told me she had put out tomato plants last summer, I was quite impressed.

    Since she was a garden-beginner, Mertie researched exactly how far apart to space her tomato plants; what kind of fertilizer to use; how to keep away the bugs, etc. Once they were planted, she took care of them daily, anxiously awaiting the juicy tomatoes to appear. But, day after day, her plants were tomato-less while all of her neighbors who had also put out tomato plants were already enjoying the fruit of their labor.

    Frustrated, Mertie gave in and went to the market to search fresh tomatoes. While paying, Mertie told the farmer her troubles. The farmer paused to think for a moment and then asked, "Well, what kind of tomatoes did you plant?"

    "I think they were called Big Boy," Mertie remembered.

    "Well there's your problem," the farmer explained. "Big Boy and Better Boy tomatoes have a 95-day growing period whereas regular tomato plants produce fruit in as few as 70 days…you just have to wait a little longer for the Big Boys."

    With that new knowledge, Mertie went home with excitement, knowing they would be worth the wait.

    Thinking about my sister's gardening experience, I had to smile. She just didn't know that Big Boy tomatoes took longer--neither did I — but once she discovered that information, she was no longer discouraged and upset about the lack of tomatoes on her plants. Instead, she was encouraged and excited to see them a few weeks later.

    It makes me wonder how many of us have "Big Boy" dreams in our hearts, yet we just don't realize that they are of the "Big Boy" variety so we are discouraged and worn out with the waiting process. Instead of waiting with excitement, we give up on our dreams and figure we must have done something wrong to stop them from coming to pass. Frustrated, we see other people's dreams coming true, and we wonder why ours haven't yet been achieved.