In 2004 ,when my daughter Becky was ten , she and my husband ,Joe, were united in their desire for a dog . As for me , I shared none of their canine lust.

    But why , they pleaded. “Because I don't have time to take care of a dog.” But we'll do it. ” Really? You're going to walk the dog? Feed the dog? Bathe the dog?” Yes, yes , and yes .”I don't believe you .” We will . We promise.

   They didn't . From day two (everyone wanted to walk the cute puppy that first day ) , neither thought to walk the dog . While I was slow to accept that I would be the one to keep track of her shots , to schedule her vet appointments , to feed and clean her , Misty knew this on day one . As she looked up at the three new humans in her life (small, medium, and large) , she calculated ,”The medium one is the sucker in the pack .”

    Quickly, she and I developed something very similar to a Vulcan mind meld (心灵融合) . She'd look at me with those sad brown eyes of hers , beam her need , and then wait , trusting I would understand — which , strangely , I almost always did . In no time , she became my feet as I read , and splaying across my stomach as I watched television .

    Even so , part of me continued to resent walking duty . Joe and Becky had promised. Not fair , I'd balk (不心甘情愿地做) silently as she and I walked . “Not fair , ” I' d loudly remind anyone within earshot upon our return home .

    Then one day — January 1, 2007 , to be exact — my husband ‘ s doctor uttered an unthinkable word : leukemia ( 白血病) .With that , I spent eight to ten hours a day with Joe in the hospital , doing anything and everything I could to ease his discomfort. During those six months of hospitalizations, Becky, 12 at the time, adjusted to other adults being in the house when she returned from school. My work colleagues adjusted to my taking off at a moment's notice for medical emergencies. Every part of my life changed; no part of my old routine remained.

    Save one: Misty still needed walking. At the beginning, when friends offered to take her through her paces, I declined because I knew they had their own households to deal with.

    As the months went by，I began to realize that I actually wanted to walk Misty. The walk in the morning before I headed to the hospital was a quiet, peaceful time to gather my thoughts or to just be before the day's medical drama unfolded. The evening walk was a time to shake off the day's upsets and let the worry tracks in my head go to white noise.

    When serious illness visits your household, it's , not just your daily routine and your assumptions about the future that are no longer familiar. Pretty much everyone you acts differently.

    Not Misty. Take her for a walk, and she had no interest in Joe's blood counts or 'one marrow test results. On the street or in the park, she had only one thing on her mind: squirrels! She Was so joyous that even on the worst days, she could make me smile. On a daily basis she reminded me that life goes on.

After Joe died in 2009，Misty slept on his pillow.

    I'm grateful一to a point. The truth is, after years of balking, I've come to enjoy m' walks with Misty. As I watch her chase after a squirrel, throwing her whole being into the here-and-now of an exercise that has never once ended in victory, she reminds me, too, that no matter how harsh the present or unpredictable the future , there's almost always some measure of joy to be extracted from the moment.

    The American Academy of Pediatrics (AAP) (儿科学) just released its updated guidelines for children's media use.

    The recommendations reflect what all parents know: children need less screen time, which indicates that they desperately need more free time to develop their imagination, a sense of wonder and discover their passion and purpose.

    Our children are over-stimulated, over-scheduled and under pressure to perform academically and beyond school. This weakens their ability to build creative thinking skills essential to self-discovery. Creativity occurs when kids have time for curiosity and exploration. With children spending up to eight hours a day on media devices and additional hours engaging in scheduled activities, opportunities for growth disappear.

    What we are not so sure about is how to get our kids to want the free, screenless time which we know will benefit them. It may sound counter-intuitive (违背直觉的) but today's kids need coaching to experience and discover the benefits of free time.

What came to parents easily a few decades ago has become a challenge for our generation. It's not that yesterday's parents knew more about child development; they simply had fewer choices. Boredom and relaxation were an inescapable part of daily life. Today, they mean, "I'm a bad parent and not doing enough to get my kid ahead."

    Recently, I had an eye-opening revelation while watching my 11-year-old daughter play in a softball game. I have six children and have attended dozens of such game. I know the drill—or thought I did. Families settled in for the day with lawn chairs, cold drinks and cousins. These brothers and sisters would gradually chat with each other. Games of catch and hide-and-seek began, and friendships were formed then. At crucial moments, the newfound friends turned their attention to the field to cheer on their teams.

    But that wasn't happening. Though there were at least 15 children by the sidelines (球场边线), I didn't hear any of them. They sat in silence using their individual tablets (平板电脑). Even with the score tied in the final inning (垒球比赛的一局), not a single child watched the game or spoke to each other. The situation was strange and revealing: Kids have more planned activities and passive entertainment at their fingertips than ever before, but less free time to dream, imagine and focus on what they truly love.

I understand that making time for "nothing" is difficult in a world where we are constantly worried our kids will fall behind if they aren't good at academics. But I refuse to sit back and watch this loss of childhood. We are taking back childhood. Imagination needs time and space to blossom.

If your kids are like mine, asking them to imagine will at the beginning be difficult. That's because they haven't developed the skills and muscle memory to make it second nature. I hope the AAP guidelines prompt all of us to set needed screen time limits for our children. Personally, I am practicing strategies to "develop imagination" in my children. Imagination, like a sport, requires practice, training, motivational speeches, rewards and extreme patience.

    Good health is the most valuable thing a person can have, but one cannot take good health for granted. It is important to remember that the body needs proper care in order to be healthy. There are three things that a person can do to help stay in good: eat right food, get enough sleep, and exercise regularly.

    Proper nutrition is important for good health. Your body cannot work well unless it receives the proper kind of “fuel”. Don't eat too much food with lots of sugar and fat. Eat plenty of foods high in protein, like meat, fish, eggs and nuts. Vegetables and fruits are very important because they provide necessary vitamins and minerals. However, don't overeat. It is not helpful to be overweight.

    Getting the proper amount of sleep is also important. If you don't get enough sleep, you feel tired and easily get angry. You have no energy. Over along period of time a little amount of sleep may even result in a change of personality. Be sure to allow yourself from seven to nine hours of sleep each night. If you do, your body will feel strong and refreshed, and your mind will be sharp.

    Finally, get plenty of exercise. Exercise firms the body, strengthens the muscles, and prevents you from gaining weight. It also improves your heart and lungs. If you follow a regular exercise program, you will probably increase your life-span. Any kind of exercise is good. Most sports are excellent for keeping the body in good shape: basketball, swimming, bicycling, running and so on are good examples. Sports are not only good for your body, but they are enjoyable and interesting, too.

    If everybody were to eat the right foods, get plenty of sleep and exercise regularly, the world would be a happier and healthier place. We would all live to be much older and wiser.

    20 years ago, a couple of ecologists, Daniel Janzen and Winnie Hallwachs, convinced Del Oro, a large orange juice producer, to donate part of their forestland to a national park in exchange for the right to dump (倾倒) massive amounts of orange peels on a 3-hectare piece of land within the national park, at no cost. Dealing with tons of waste peels usually involved burning them or paying to have them dumped at a landfill, so the proposal was very attractive.

    A year after the contract was signed, Del Oro dumped around 12,000 tons of sticky orange waste in the land. However, another juice company and rival of Del Oro challenged the deal in court, arguing that their competitor was “polluting the national park”. They ended up winning, and the deal between Del Oro and the national park fell through. The 3-hectare piece of land virtually covered with fruit waste was completely forgotten.

    Then, in 2013, Timothy Treuer, a scientist at Princeton University visited that piece of land 15 years earlier. What he found shocked him. “It was completely overgrown with trees and vines,” Timothy Treuer recently said, “the difference between fertilized and unfertilized areas was visually surprised us a lot! We needed to come up with some really good standards to evaluate exactly what was happening there.”

    To confirm that the fruit waste was responsible for the revival of plant life, Treuer and his team spent months picking up samples, analyzing and comparing them. They found “dramatic differences between the areas covered in orange peels and those that were not. The area fertilized by orange waste had richer soil, greater tree-species richness and greater forest coverage. In a sense, it's not just a win-win between the company and the local park—it's a win for everyone.”

    The effect the orange peels had on the land is probably not that surprising to people familiar with composting (堆肥), but what is shocking is that a judge actually called this particular example polluting the national park and stopped it from going forward. Now that Timothy Treuer's study has received worldwide attention, this type of polluting is being seriously considered as a way of bringing tropical forests back to life.

    Cao Yuan, a PhD student from China, had two papers published on strange behaviour in atom-thick layers of carbon that have opened up a new field of physics.

    Pablo Jarillo-Herrero's group at MIT was already layering and rotating (旋转) sheets of carbon at different angles when Cao joined the lab in 2014. Cao's job was to find out what happened when one graphene (石墨烯) sheet was twisted only slightly wiht respect to the other, which one theory predicted would thoroughly change the material's behaviour.

    Many physicists doubted the idea. But when Cao set out to create the subtly twisted stacks, he spotted something strange. Exposed to a small electric field and cooled to 1.7 degrees above absolute zero, the graphene—which ordinarily conducts electricity—became an insulator. That by itself was surprising. But the best was yet to come: with a slight change to the field, the twisted sheets became a superconductor, in which electricity flowed without resistance.

    The ability to get atom-thick carbon into a complex electronic state through a simple rotation now has physics demanding to engineer exciting behavior in other twisted 2D materials. Some even hope that graphene could shed light on how more-complex materials superconduct at much higher temperatures. "There are so many things we can do," says Cory Dean, a physicist at Columbia University. "The opportunities at hand now are almost irresistible."

    Hitting graphene's “magic angle”—a rotation between parallel sheets of around 1.1°—involved some trial and error, but Cao was soon able to do it reliably. His experimental skill was extremely important, says his supervisor Jarillo-Herrero. Cao pioneered a method of tearing a single sheet of graphene so that he could create a stack of two layers, from which he could then fine-tune alignment (微调校准).

    Cao loves to take things apart and rebuild them. A heart, he is “a tinkerer”, his supervisor says. On his own time, this means photographing the night sky using homemade cameras and telescopes—pieces of which usually lie across Cao's office. "Every ime I go in, it's a huge mess, with computers taken apart and pieces of telescope all over his desk," says Jarillo-Herrero.

Teaching Poetry

    No poem should ever be discussed or "analyzed", until it has been read aloud by someone, teacher or student. Better still, perhaps, is the practice of reading it twice, once at the beginning of the discussion and once at the end, so the sound of the poem is the last thing one hears of it.

    All discussions of poetry are, in fact, preparations for reading it aloud, and the reading of the poem is, finally, the most telling "interpretation" of it, suggesting tone, rhythm, and meaning all at once. Hearing a poet read the work in his or her own voice, on records or on film, is obviously a special reward. But even those aids to teaching can not replace the student and teacher reading it or, best of all, reciting it.

    I have come to think, in fact, that time spent reading a poem aloud is much more important than "analysing" it, if there isn't time for both. I think one of our goals as teachers of English is to have students love poetry. Poetry is "a criticism of life", and "a heightening of lief". It is "an approach to the truth of feeling", and it "can save your life". It also deserves a place in the teaching of language and literature more central than it presently occupies.

    I am not saying that every English teacher must teach poetry. Those who don't like it should not be forced to communicate this to anyone else. But those who do teach poetry must keep in mind a few things about its essential nature, about its sound as well as its sense, and they must make room in the classroom for hearing poetry as well as thinking about it.