Bursting into the classroom from recess, 15 children take their seats and face the woman they know as Ms. Yang.

    “What day is it today?” she asks, in Mandarin Chinese.

    “Confucius' birthday!” the fifth graders shout in Mandarin.

    “Why do we celebrate Confucius' birthday?”

    “Because he's the greatest teacher in the history of China!” exclaims a brown-haired girl. She is speaking Mandarin.

    English is rarely heard in Lisa Yang's class at the Chinese American International School(CAIS), despite the fact that few students are native speakers of Mandarin.

    The United States is actively trying to increase the group of students in “critical languages” such as Mandarin. The students at CAIS are way ahead in such a trend.

    Founded 25 years ago, this small private school in San Francisco, USA, does what few other American schools do: It produces fully fluent speakers of Mandarin Chinese, by far the most commonly spoken language in the world.

    Mandarin Chinese is suddenly hot in American schools. As China becomes the world's leading economy sometimes this century, schools in the U. S. are scrambling to add Mandarin to their list of foreign languages or expand Chinese programs already in place.

    “It really is almost unprecedented. People are looking at China as a force to be reckoned with… And to ensure that the U. S. has the ability to conduct trade, and to work with the Chinese. Certainly having an understanding of Chinese language and culture is an advantage,” said Marty Abbott of the American Council on the Teaching of Foreign Languages(ACTFL).

    To develop Chinese-language programs has not been smooth. A shortage of trained teachers has made it difficult for some schools to join the race. When schools do get teachers, they often hire them straight from China, and the teachers usually suffer culture shock when they come to the U. S.

    Robert Liu remembers his first two years in an American classroom It was not an easy adjustment. “In China, students respect their teachers,” he said. Liu found that American students, however, expect an active teaching style. He had to use games to engage them rather than lectures.

    To avoid many of the problems with foreign teaching styles, the CAIS has been working with the Chinese government to improve training of teachers who are sent to the U. S.

    “There's a mother in PICU(儿童重症监护病房)who wants to talk about a kit she received,” the nurse told me. “Something about it made her cry.”

    I've been a child-1ife specialist at the Cleveland Clinic Children's Hospital since 2000. I help families understand diagnoses and treatment plans and manage the ups and downs that come with caring for a sick child. Tough talks with parents are part of the job, which still makes me feel nervous.

    The kits the nurse was talking about were something I had recently introduced to the hospital: Comfort Kits from Guideposts. They were supposed to make a child's experience here easier, not upsetting.

    When I came across the kits at a conference. I fell in love with them. A treasure box of items designed not only to entertain kids, but to comfort and inspire them. There's a coloring book, a stress ball, a CD of relaxing music, a hairy star named Sparkle, a journal and much more. I really believed these kits would help kids. I wished I hadn't been mistaken.

    At the patient's room in PICU I saw a little girl, sleeping soundly, surrounded by tubes and machines. My eyes met her mother's. The kit was open on her lap and tears were running down her cheeks.

    “I'm Shannon. I manage the Child Life Department.” I said. “I'm sorry if the kit upset you .It's a new item…”

    The mother shook her head. “This has been one of the worst days of my life .I felt so scared and alone. Then I was handed this box. I know it's for my daughter, but it's just the comfort I needed. I wanted to say thank you.”

    With that I knew Comfort Kits belonged here. We've been using them for almost three years now. Each child who's admitted to the hospital receives one. Every day I see kids coloring, journaling, playing with Sparkle.

    But as this mom showed me Comfort Kits aren't just for kids. The hope they bring, which can be in short supply in hospitals sometimes, is felt by the whole family.

    Scottish pupils recently were part of a new scheme that allowed them to take their exams online. Those examinations provided a glimpse of the future in May when 120 candidates in 10 centers in Scotland sat in front of computers to take a multiple-choice online exam. Although candidates were using a computer mouse instead of a pen, in all other ways the exam was the same as normal.

    Exam rooms were set out to ensure that only the candidates and the teachers were able to see the individual screens. The online answers were sent directly to a safe area. According to the students at St Ninian's in East Renfrewshire who took an online French exam, it was definitely the most motivated they had ever felt when taking an exam.

    “I could go as fast as I wanted to, rather than as slow as everyone else wanted to,” said one. “It was better than looking back and forth between the questions,” said another. One pupil even described it as fun.

    Their head teacher, Dorothy Graham, was not so surprised, “They are so used to doing things on computers that it seems natural for them. The boys liked it because they didn't have to worry about how neat their work was.” The only things that worried her were power cuts and systems' crashing.

    It's thought that online exams could be the norm (常态) in about five years. However, last year there were warnings about computerizing exams in England and Wales. It's thought that it could be unfair to some students if they come from homes without access to a computer.

    Getting rid of dirt, in the opinion of most people, is a good thing. However, there is nothing fixed about attitudes to dirt.

    In the early 16th century, people thought that dirt on the skin was a way to block out disease, as medical opinion had it that washing off dirt with hot water could open up the skin and let illnesses in. A particular danger was thought to lie in public baths. By 1538, the French king had closed the bath houses in his kingdom. So did the king of England in 1546. Thus it began a long time when the rich and the poor in Europe lived with dirt in a friendly way. Henry IV, King of France, was famously dirty. Upon learning that a nobleman had taken bath, the king ordered that, to avoid the attack of disease, the nobleman should not go out.

    Though the belief in the merit of dirt was long-lived, dirt has no longer been regarded as a nice neighbor ever since the 18th century. Scientifically speaking, cleaning away dirt is good to health. Clean water supply and hand washing are practical means of preventing disease. Yet, it seems that standards of cleanliness have moved beyond science since World War Ⅱ. Advertisements repeatedly sell the idea: clothes need to be whiter than white, cloths ever softer, surfaces to shine. Has the hate for dirt, however, gone too far?

    Attitudes to dirt still differ hugely nowadays. Many first-time parents nervously try to warn their children of touching dirt, which might be responsible for the spread of disease. On the contrary, Mary Ruebush, an American immunologist(免疫学家), encourages children to play in the dirt to build up a strong immune system. And the latter position is gaining some ground.

    Imagine putting a seed in a freezer, waiting 30,000 years, and then taking the seed out and planting it. Do you think a flower would grow?

    Amazingly, scientists have just managed to do something very similar. They found the fruit of an ancient plant that had been frozen underground in Siberia—a region covering central and eastern Russia—for about 31,800 years. Using pieces of the fruit, the scientists grew plants in a lab. The new blooms have delicate white petals. They are also the oldest flowering plants that researchers have ever revived from a deep freeze.

    “This is like regenerating a dinosaur from tissues of an ancient egg,'' said Jane Shen-Miller, a biologist of University of California, Los Angeles.

    The plant has a long history. Back when mammoths and woolly rhinoceroses walked on the land, an Arctic ground squirrel buried seeds and fruits in an underground chamber near the Kolyma River in northeastern Siberia. The ground became pennafrost, a layer of soil that stays frozen for a long time.

    Recently, Russian scientists dug out the old squirrel hole and found the plant remains 38 meters below the surface. Back at the lab, the team fed nutrients to tissue from three of the fruits to grow shoots. Then the scientists transferred the shoots to pots filled with soil. The plants produced seeds that could be used to grow even more of them.

    It's important for scientists to know that plant tissues can still be revived after being frozen for a long time. That's because many researchers are trying to preserve the seeds of modem plants by freezing them and then storing them in giant lockers at various spots around the globe. One such endeavor, an underground facility in Norway, is called the Svalbard Global Seed Vault. It stores hundreds of thousands of frozen seeds. If a plant ever goes extinct, scientists could bring it back by taking its seeds from the Svalbard or other storage lockers.

    "No one knows how long they are able to live for, but freezing is basically the format for many plant conservation attempts nowadays," Jane Shen-Miller said. It's a good thing that at least some plants are tough enough to survive in the experience.

    Every man dreams of having agood car. With luxury cars, like Bentley, Lamborghini and Rolls-Royce, going intothe world of SUVs, if you have deep pockets, you will be spoilt for choice.

    ◆Lamborghini Aventador SVJ

    Using a new aerodynamic system allows it toset a car lap record of 6: 44 97 at Nurburgring, one of the longest and most challengingcircuits in the world. Plus, carbon fiber can be seen everywhere, which makes thecar strong and lightweight. There're only 900 being built and you'llneed to coughup $517, 770 to buy one.

    ◆Aston Martin DBX

    The DBX is Aston Martin's maiden SUVproduct. It features a choice of two gas engines—a 4.0-liter V8 from Mercedes anda 5.2-liter V12 from its own. The price is predicted to be around $250, 000.

    ◆Audi E-tron

    Being an eco-friendly motoring, it is an all-electricSUV that makes up for its rather ordinary appearance with design, luxury and technology.At the front and back are electric motors which insure progress is rapid. In additionto plenty of storage space, the Audi E-tron provides side cameras instead of sidemirrors and air suspension that adapts to the terrain (地形). Hand over $74, 800 and it's yours.

    ◆Tesla Roadster

    Tesla Roadster will turn most heads, Zero to60 in 1.9 seconds means it will leave most cars for dust. The top speed is 250 mph,which is also unheard of for most cars—let alone an all-electric one. Having advancedautonomous driving systems and a huge touchscreen for surfing the Internet, it won'tmake you regret for paying $200, 000.