My folks bought their first house in the early 1940s after Dad got a better job in Marquette, Michigan. We lived just inside the city limits in what was still a rural area.

    In the spring of 1948, when I was 6 years old, my parents bought a calf (小牛) to replace our cow, which had been killed the year before. So one day we drove to a local farm and returned with a white and brown calf we named Tubby.

    We didn't own a truck, so Tubby rode home in the backseat of Dad's car with my 9-year-old brother Steve, and me. As you can imagine, the trip was a lot of fun for us kids.

    Later that summer, Mom thought it would be cute to take a picture of me sitting on Tubby's back. All went well unti1 the snap of the camera shutter sent Tubby charging off on a run, with me holding on for dear life. I lasted for about 30 feet before I hit the ground. Mom was quick enough to shoot a follow-up picture, so we had photos of me both on and off Tubby!

    When summer had passed, the day arrived for poor Tubby to fill our freezer I must have been somewhere else with my Mom on the fateful day, because I have no memory of how it happened. All I knew was that the barn was empty, and that we had plenty of meat for dinners.

    I hadn't lived on a farm like my mother, so I didn't understand that what happened to Tubby was not unusual. Livestock aren't meant to be pets, and most farm kids know and accept that truth.

    Whenever we had beef for dinner, I would tearfully, “Is this Tubby” This went on for a couple of weeks until Dad had finally had enough and declared, “No more cows!” That made me feel a little better about poor Tubby.

    As I stood in the return line and watched people, I became extremely impatient. My daughter had got four Barbie dolls and two identical Cabbage Patch Kids on Christmas, so I was eager to return toys that she didn't need. Suddenly a strong idea came to me. I eyed the lady in front of me with three small girls on her leg. The family looked poor. The children were without coats, and they had dirty faces and hair. “You are ready to get out of here, aren't you? Give her the things you want to return,” the still voice spoke. “Give them to her? These are mine. I'm not giving her my stuff,” I argued. I swallowed the urge that threatened to escape my lips when the voice spoke again. “Give her the toys.” I was familiar with the voice. I know I couldn't argue with that voice.

    I sighed and tapped the lady on the shoulder. “Ma'am,” I cleared my throat. She looked at me with kind, tired eyes surrounded by wrinkles. “Yes?” she asked. “Would your little girls like to have these toys?” I pointed to my basket full of returns. “Would your children like to have them?” She was speechless, and I swore that tears were about to well up in her eyes. “You'd be doing me a favor. I can't stand in this line in a moment longer.” “You have no idea,” she shook her head. “You have no idea what that means to me.”

    I started loading her basket as the excited girls watched. “Merry Christmas,” I said, “God bless you.” She replied as I nodded and exited the line. I didn't want to go the Walmart that day, but I went. I didn't want to give the lady my kid's toys, but I did. Sometimes doing what we don't want to do is exactly what we're supposed to do.

    The full moon climbs over the eastern horizon (地平线) and hangs like a huge orange globe in the sky. A few hours later, the moon is overhead but seems to have changed. The huge orange globe has become a small silver disk. What has happened? Why has the orange color disappeared? Why does the moon seem so much smaller and farther away now that it is overhead?

    The moon appears orange on the horizon because we view it through the dust of the atmosphere. The overhead moon does not really shrink as it moves away from the horizon. Our eyes inform us that the overhead moon is farther away. But in this position the moon is actually closer to our eyes than when it is near the horizon.

    The change in size is a trick our eyes and minds play on us. When the moon is low in the sky, we can compare its size with familiar objects. It is easy to see that the moon is much larger than trees or buildings, for example. When the moon is high in the sky, however, it is hard to compare it with objects on earth. Compared to the vastness of the sky, the moon seems small.

    There is another reason why the moon seems to shrink. We are used to staring at objects straight ahead of us. When an object is difficult to see, our eyes have to try to focus on it. When we move our heads back to look up, we will try hard again. Looking at something from an unaccustomed position can fool you into believing an object is smaller or farther away than it is. However, scientists do not yet understand completely why the moon seems to shrink as it rises in the sky.

    For most of my 20 years as a teacher, summer vacation was my time to relax. So why was I standing in the schoolyard of an unfamiliar school, wearing myself out for a summer teaching job? The extra paychecks were nice, but I lacked the energy of my younger colleagues. Like Stella. She was in her early twenties, and made keeping up with the kids look effortless. She reminded me of myself, back when I was a bright-eyed student teacher at Ramona Elementary…

    I'd never forget my first day. I was too full of energy. Nervous energy. My supervising teacher was watching, and I wanted to make a good impression. I asked my third graders to take out their crayons for the day's lesson. All of them obeyed. Except one. A girl with two long, dark braids(辫子). Everyone called her Estrellita, or “little star.” Why was she unprepared for class? I demanded to know.

    “My sister has my crayons,” she said.

    “You should each have your own crayons,” I told her. “That's no excuse.”

    “There are 10 children in my family,” Estrellita said quietly, her big brown eyes never leaving my face. “We have to take turns.”

    I was taken aback. I'd completely misjudged the situation. All day Estrellita's words played on my mind. The next morning I bought a pack of crayons to leave on Estrellita's desk. She was so happy! That experience taught me an important lesson. Every student had a unique set of challenges—it was my mission to help my students overcome them. That mission used to energize(激励 )me.

    Rest was almost over. Stella turned to me and we started chatting. “How long have you been teaching?” she asked. I told her I'd started twenty years before, at Ramona Elementary.

    “I went to school there twenty years ago!” Stella said. I looked at her again, this time really seeing her. Those big brown eyes. That long, dark hair...

    “Did you use to have two long braids?” I said. “We called you Estrellita… ”

    Stella shouted. “ You ! You gave me the crayons!”

She'd become a teacher. To help students like I did. Even doing something that small mattered.

    That summer, I threw myself into teaching with a renewed sense of purpose. Estrellita had taught me a lesson once again.

    English teenagers will receive cooking lessons in schools. The idea is to encourage healthy eating to solve the problem that many people are overweight. Also, it worries people that basic cooking and food preparation skills are being lost because parents use too much pre-prepared fast food.

Cooking was once regarded as an important part of education in England—even if it was mainly for girls. In recent years cooking has become less important in schools. But the rising level of obesity has led to rethink about the food that children are given and the skills they should be taught.

    “What we want is to teach young people how to do basic, simple meals, which they can use now at home and then in their life,” said Ed Balls, an education expert.

    The new lessons will start in September, but some schools without kitchens will be given a longer time to prepare. Also, there may be a shortage of teachers with the right skills, since schools have been teaching food technology rather than practical cooking. Besides, the lessons for hand-on cooking will only be one hour a week for one term. But the well-known cookery writer, Pru Leith, believe it will be worth it.

    “If we'd done this thirty years ago we might not have to face the problem about obesity and lack of knowledge about food and so on. Every child should know how to cook, not just so that they'll be healthy, but because it's a life skill which is a real pleasure.”

    The renewed interest in cooking is an effort to reduce the obesity rate, which is almost the highest in Europe, and according to the government, half of all British people will be obese in 25 years if present trends are not halted.

    What if we could replace oil with a fuel which produced no pollution and which everybody had equal access to? The good news is that we can, in fact, we are swimming in it -literally.

    Hydrogen is one of the building blocks of the universe. Our own sun is basically, a big，dense cloud of the stuff. And hydrogen can be used to create electricity for power, heat and light.

    The problem is that hydrogen is everywhere and nowhere at the same time. It does not exist as a material on its own, but is always part of something else. So it has to be separated before it can be used.

    Most commercial hydrogen in use now is created from natural gas. As oil will start to run out in around the year 2030. It makes sense to produce as much hydrogen as possi­ble as soon as we can. But natural gas supplies will also begin to run out soon after. Another source is needed.

    Researchers are now using electricity to make water into hydrogen. Companies are working on the problem in their own areas. The first commercial hydrogen "fuel cells" for computers and mobile phones have already come on to the market Auto companies have also invested over US $2 billion in the production of hydrogen fuelled cars.

    The nations of a hydrogen fuelled planet would not fight over energy recourses. There would be a great reduction in pollution, the only by-product of creating hydrogen is pure drinking water something that is very scarce in many parts of the world. But that is not where the good news ends, once the costs of producing hydrogen have been brought down, it will possibly provide power for a third of the Earth's popula­tion that has no electricity.

    And electricity creates wealth. In South Africa over the last decade there has been a large programmer of electrification. Thanks to the programmer, people do not have to spend their days looking firewood to burn for heat and with electric light, they can work long into the night

Some scientists see radical changes in the way the human race co-operates. Hydrogen creates electricity, and is also created by it. With dual use fuel cells, everyone who consumes energy could also produce it. Late at night, a man drives home in London and connects his car into the "worldwide hydrogen web", which it supplies with electricity. A few hours later, a man in Beijing uses that electricity to power the hydrogen cell in his car. Hydrogen could be the first democratic energy source.

    Like all dreams of the future, it seems very far away. But the threat of war and terrorism in the Middle East has made governments and businesses more aware of the need to end oil dependency and spend more time and money on hy­drogen resource. So maybe the threat of war is not a completely bad thing for the future of the human race.