Lots of people buy books and products from Amazon, an online seller. They offer and pay over the Internet and the books are shipped through the mail or a delivery service like FedEx.

    One day, people could get their Amazon deliveries from an “unmanned aerial vehicle”—a timely vehicle that looks like a toy helicopter. And instead of waiting days to get the parcel, it could be at the buyer's home in half an hour or less. The company is working on a fleet of tiny vehicles they call “Prime Air”. The vehicles are also known as “octocopters”. On their website, Amazon says, “One day, Prime Air Vehicles will be as normal as seeing a mail trucks on the road today.”

    The U.S.'s Federal Aviation Administration (FAA) is working on safety regulations for unmanned flying vehicles like the Prime Air copters. Those regulations will make sure the copters are able to fly safely where they need to go. Once the FAA has put its rules in place, which could be as early as 2016, Amazon will be ready with its fleet of tiny flyers. The process could take as many as five years.

    The new delivery service would likely be available only in the United States, at first. The copters the company is testing now can handle packages up to five pounds (2.3kg) and they have a range of 10 miles (16 kilometers).

    Other companies are also looking at using unmanned flying vehicles to deliver their products. For instance, Domino's Pizza in the U.K. released a video showing a “DomiCopter”, delivering a pizza. That video may have been a publicity stunt（噱头）. In any case, just like Prime Air's octocopters, the DomiCopters don't have clearance（许可）to take off just yet.

    Nov. 21 is World Hello Day. It began back in the 1970s as part of an effort to make the world more peaceful. It was created by the United Nations just after the war between Israel and Egypt in 1973. The philosophy (理念) behind it is: Say “Hello” and stop war.

    It sounds like a fine idea, but most of us know that simply saying “Hello” won't bring about world peace. Still, on a smaller range, the simple act of saying hello to someone can make a lot of difference.

    This might not be obvious. After all, it's such a casual thing and requires so little effort. You raise your head to someone as you pass by them in the school corridor (走廊), say “Hello' then it's over.

    Although we might not realize it, a small thing like a greeting can mean a lot to a person. Many people are lonely because they're shy. They find it difficult to communicate with people, even though they want lo. It leads to them feeling cut off.

    On this basis, maybe it's a good idea, not just on Nov. 21, but every day, to remember to say “Hello” to as many people as we can. The stranger who hears your greeting may secretly smile in their heart. You might even make their day.

    Greeting other people is the easiest way to be polite. Politeness is the way we individual humans link up with the rest of the human world outside of our circles of family and friends. Politeness is one of the aspects of culture that make us a society rather than just many individuals living in the same space.

    No one said it better than the French author Joseph Joubert: “Politeness is the flower of humanity''. A “Hello” to a stranger is a small thing, and often neglected (忽视), but through it we can make the world better for another person.

    The computer keyboard helped kill shorthand—a system of rapid handwriting, and now it's threatening to finish off handwriting as a whole. When handwritten essays were introduced on the SAT exams for the class of 2012, just 15% of the most1.5 million students wrote their answers in cursive(手写体). The rest? Block letters.

    And those college hopefuls are just the first edge of a wave of US students who no longer get much handwriting instructions in the primary grades, frequently 10 minutes a day or less. As a result, more and more students struggle to read and write cursive.

    There are those who say the culture is at a crossing, turning from the written word to the typed one. If handwriting becomes a lost form of communication, does it matter?

    It was at University Virginia that researchers recently discovered a previously unknown poem by Robert, written in his unique script. Handwritten documents are more valuable to researchers, historians say, because their authenticity can be confirmed. Students also find them more fascinating.

    The loss of handwriting also may be  a cognitive(认知的) opportunity missed. Several academic studies have found that good handwriting skills at a young age can help children express their thoughts better—a lifelong benefit.

    It doesn't take much to teach better handwriting skills. At some schools in Prince George's County, elementary school students use a program called Handwriting Without Tears for 15 minutes a day. They learn the correct formation of manuscript (手写的)letters through second grade, and cursive letters in third grade.

    Five-year-old Prisilla Perez, a student at Meador Elementary School in Willis, was unhappy with her recent haircut, which resulted from a severe disease. When students in her class started calling Prisilla a boy, she felt ashamed, often crying and losing focus in school.

    Her teacher, Shannon Grimm, sympathized with her unhappiness. Grimm and Prisilla's mom were concerned, but their ideas didn't work. “We had classroom discussions about how girls have short hair and boys have long hair, and I showed them photos of movie stars with different looks,” Grimm said. “However, it wasn't sinking in.”

Grimm thought about Prisilla throughout winter break, and one morning, she had an idea: Cut off her hair — a scary thought for Grimm, who wore her hair long and took pride in it. “I've never had short hair, and I stressed about it for two weeks before making a decision,” she said. On Jan. 4, Grimm invited a hairstylist friend to her home. “I told him to keep going, even if I cried,” she said.

    The class loved their teacher's new do, especially Prisilla, who excitedly ran off the school bus that afternoon yelling, “Mom, Ms. Grimm cut her hair!” The teacher also bought matching bows for herself and the girl, so they could style their hair together.

    In February, the teacher recommended Prisilla for the school district's Student of the Month Award, but during the Monday ceremony, she received a surprise “hero medal” from the girl. “Now we have matching awards,” says Grimm.

Prisilla's mother, Maria, said that Grimm's thoughtfulness brought her to tears. “I was shocked. I was crying. I couldn't believe it — she did something I wouldn't have the bravery to do. I will never forget that.”

    The term "crocodile tears" refers to insincere sadness. This term has an etymology dating back several centuries. As early as the fourth century, crocodile tears are referenced in the literature with the meaning of insincere sorrow. It is said that crocodiles weep while eating their hunted animals because they are sad; however, this sadness is not honest.

    The term crocodile tears became widely popular after it was documented in a fifteenth-century book titled The Voyage and Travel of Sir John Mandeville, Knight. A passage from the book reads: "These crocodiles kill men and they eat them weeping."

    As you may already know, crocodilians(鳄目动物) likely feel bad about little—especially feeding. However, the assumption of the crocodile-tears metaphor may be true. In a 2007 paper published in BioScience titled "Crocodile Tears: And they eat them weeping", researchers observed 7 crocodilians in cages during feeding time at a reserve (4 caimans and 3 American alligators). The researchers observed the crocodilians outside of water at feeding stations to better find out whether tearing developed.

    Five of the 7 crocodilians developed something like tears in their eyes before, during or after feeding. The researchers suggest that these crocodile tears occur because a crocodilian hisses (发出嘶嘶声) while it eats, and this hissing forces air through the spaces in the bone behind the nose and out the eye, in the process picking up nasolacrimal secretions (鼻泪管分泌物.)

    In humans, crocodile tears is a medical condition that causes a person to tear up while eating. Crocodile tears typically occur because of a temporary loss of facial control due to damage of the facial nerve. Specifically, when the facial nerve grows again, it does so incorrectly thus resulting in tears during chewing food.

Despite extreme cold, cruel ice and being brushed off as mad, Slovenian Davo kamicar became the first person to ski non-stop down Mount Everest. After a dramatic fall over almost sheer cliffs of snow, stones and ice, 38-year-old Kamicar returned to his base camp after five hours of skiing. "I feel only absolute happiness and absolute tiredness," he said. 

Due to the severe weather conditions, Kamicar flung himself back down the mountain as soon as he reached the top rather than have a rest as planned At one point, he had to speed overstretches of ice that collapsed and broke underneath him and could have sent him falling into the deep crevasses(裂缝) that dot the mountain.

The descent (下落) had been widely regarded as extremely dangerous. The Darwin Awards website, known for documenting foolhardy deaths, urged people to log on to their website and "keep your eyes peeled for a live Darwin Award". However, the only body to make the news was the corpse (尸体)of an unknown mountaineer which Kamicar zipped past as he descended one of an estimated 120 corpses, thought to litter the slopes." This mountain is always full of surprises. Seeing a dead man out there was still a shocking experience," he said. 

Thanks to strategically placed cameras on the mountain and one attached to his safety helmet hundreds of thousands of people witnessed the process online, which was one of the record highs ever of more than 650,000 hits. The website was once jammed as people tried to access the site.

A previous failed attempt had already cost Kamicar two fingers when he got frostbite as a fierce storm hit the peak. Coming from a skiing family and had his first Himalayan skiing expedition in 1989, he has been ever since tireless in raising funds and sponsorship for more expeditions, with Everest as the permanent goal.