We already know the fastest, least expensive way to slow climate change: Use less energy. With a little effort, and not much money, most of us could reduce our energy diets by 25 percent or more—doing the Earth a favor while also helping our wallets.

    Not long ago, my wife, PJ, and I tried a new diet—not to lose a little weight but to answer an annoying question about climate change. Scientists have reported recently that the world is bending up even faster than predicted only a few years ago, and that the consequences could be severe if we don't keep reducing emissions(排放) of carbon dioxide (CO₂ ) and other greenhouse gases that are trapping heat in our atmosphere.

    We decided to try an experiment. For one month we recorded our personal emissions of CO₂. We wanted to see how much we could cut back, so we went on a strict diet. The average US household(家庭) produces about 150 pounds of CO₂  a day by doing common-place things like turning on air-conditioning or driving cars. That's more than twice the European average and almost five times the global average, mostly because Americans drive more and have bigger houses. But how much should we try to reduce?

    For an answer, I checked with Tim Flannery, author of The Weather Makers: How Man is Changing the Climate and What it Means for Life on Earth. In his book, he had challenged readers to make deep cuts in personal emissions to keep the world from reaching extremely important tipping points, such as the melting(融化) of the ice sheets in Greenland or West Antarctica. "To stay below that point, we need to reduce CO₂  emissions by 80 percent," he said.

    Good advice, I thought. I'd opened our bedroom windows to let in the wind. We'd gotten so used to keeping our air-conditioning going around the clock. I'd almost forgotten the windows even opened. We should not let this happen again. It's time for us to change our habits if necessary.

    Wherever she goes, Molly leaves her mark. Without saying a word, she speaks to people with her kind eyes. Even when she walks away, she leaves an impression. Molly's mark is a smile, stamped into the ground by the horseshoe at the bottom of her false leg．

    A few years ago, Molly was badly attacked by a dog. The dog bit all four of Molly's legs and left large cuts in her face. Molly's owner, Kate Harris, took her to an animal hospital. Doctors there were able to save Molly's life, but soon one of her legs became very infected (感染).

    At first, doctors thought Molly would have to be put to sleep. But Molly changed their minds. This pony, doctors noticed, shifted her weight, and rested her good leg from time to time. Doctors knew that Molly had amazing intelligence, and that she wanted to live.

    Several doctors operated on Molly, and removed her infected leg. A false leg was made for her. The leg was a hollow cast with a pole at the bottom for balance. Doctors gave Molly a special horseshoe at the bottom of the leg. This horseshoe she had had a stamp of a smile face in it!

    After the operation, Molly walked around on all four legs, as if nothing had ever happened to her! Now, with every step she takes, she stamps a smile in the dirt. But she leaves her mark in other ways, too.

    Kaye Harris took Molly to the false leg center. There were children there who, like Molly, had artificial arms or legs. They were amazed to see a pony with a false leg. Molly made them smile and gave them hope. Soon, Molly began to visit schools, nursing homes, army bases and hospitals. A book was even written about Molly!

    Children often suffer pain and insecurity when their parents separate.When my ex-husband and I split up after 10 years of marriage,our daughter was 5 years old and my son only 3.We decided to consult a psychologist about the best way to explain this new situation to the children.

    She shared with us this special story about a land turtle and a sea turtle,which we then used to help them better comprehend. Once upon a time,a land turtle (Mommy) met a sea turtle (Daddy) close to a beautiful shore.Soon they fell deeply in love and decided to get married.For a time,they continued to live at the water's edge so that Mommy could sit on the sand and keep dry and warm,while Daddy sat in the shallow water to keep cool.A few years later two baby turtles arrived (you both!).They were very special indeed and looked a little like each of their parents.

    But as the years went by,Daddy sea turtle started spending more and more time in the ocean as he traveled deeper and deeper to look for pearls.Mommy land turtle also started wandering up into the sands to hunt for food in the woods.Little by little,Daddy and Mommy turtle started to drift further and further apart.Finally one day,Mommy and Daddy turtle decided they didn't want to live together anymore.The little turtles continued to spend time with each of their parents.They made lots of friends with all the fish,dolphins and whales in the ocean and also many friends with the rabbits,deer,and foxes in the woods.In fact they grew up to be a new kind of turtle that could live both in the ocean and on the land.

    Over the years,this tale of the land and sea turtle has helped my children cope with and accept the fact that my marriage to their father was over.They know that we once loved each other very much and they were born out of true love.

    A Swiss airplane powered only by energy from the sun left from Abu Dhabi early on March 9. Its creators hope the plane will make the first around-the-world journey without any fuel. The plane is called Solar Impulse 2. It has one seat and is made from carbon fiber. The plane weighs only as much as a car but its wings are wider than a Boeing 747. The plane's wings stretch 72 meters across. Those wings include 17,000 solar units, or cells, which capture the sun's energy. The energy allows the plane to fly day and night.

    Two Swiss scientists built the plane. Bertrand Piccard is also an explorer who made the first non-stop flight around the world in a balloon. Andre Borschberg is an engineer and trained fighter pilot. The scientists say they are not trying to alter the airplane industry. Instead, they want to show that new energy sources and technologies can achieve what some say is impossible. “We want to show we can fly day and night in an aircraft without a drop of fuel.” Mr. Piccard said.

    Some parts of the trip will require the pilots to be in the tiny plane for five to six days and nights in a row. So it is good that the pilot's seat is also a toilet.

    The plane's route begins in the United Arab Emirates. The pilots also plan stops in Oman, India, and China. They will cross the Pacific Ocean, stop in the United States, and continue over southern Europe or North Africa. They plan to arrive back in the United Arab Emirates in late July or early August.

    Internet viewers can go to the Solar Impulse website to see the plane's location and listen to broadcasts from the pilots.

    Katherine Johnson, a brilliant mathematician at NASA (美国宇航局), began working on the space program in the 1950s. Many of NASA's first missions were made possible by her amazing calculations (计算).

    As a child, she loved to count. Her father placed great importance on education and insisted all four of his children go to college, working overtime to pay for it. Johnson said this atmosphere was important to her success. "I was always around people who were learning something. I liked to learn." She said.

    Johnson graduated from high school at 14 and college at 18. In 1953, Johnson started to work for NASA, doing the math that powered engineers' work. Then, because of her outstanding talent, she was moved to work on rockets with an all-male flight research team. As for Johnson, her calculations contributed to many of NASA's most important projects. In 1961, with the help of Johnson's work, Alan Shepherd became the first American to go into space. Johnson also lent her unbelievable talent to the success of the Apollo 13, which had trouble getting back to earth. She worked hard to calculate a safe path back to Earth for the astronauts.

    Johnson retired in 1986, but her huge contribution to the space program has only been reaching the public attention for the past few years. Part of that is because, as she is the first to admit, science is based on collaboration. "I never took any credit because we always worked as a team, it was never just one person," she said in a 2010 interview.

    Earlier this year, NASA named a new data center after her. She was also given a Silver Snoopy award, which recognizes "outstanding performance, contributing to flight safety and mission success."

    I attended a party one night. During the dinner a man told a humorous story based on the quotation: "There's a divinity that shapes our ends, rough-hew them how we will."

    The storyteller mentioned that the quotation was from the Bible. I knew he was wrong. There couldn't be the slightest doubt about it. To get a feeling of importance and display my superiority, I appointed myself as an unwelcome committee member to correct him. He stuck to his guns. "What? From Shakespeare? Impossible! Absurd! That quotation was from the Bible." And he knew it.

    The storyteller was sitting on my right; and Frank Gammond, an old friend of mine, was seated on my left. Mr. Gammond had devoted years to the study of Shakespeare. So the storyteller and I agreed to submit the question to Mr. Gammond. Mr. Gammond listened, kicked me under the table, and then said, "Dale, you are wrong. The gentleman is right. It is from the Bible."

    On our way home that night, I said to Mr. Gammond, "Frank, you knew that quotation was from Shakespeare. "Yes, of course," he replied, "Hamlet, Act Five, Scene Two. But we were guests at a happy time, my dear Dale. Why argue with the storyteller? Why prove to him he is wrong? Why not let him save his face? Always avoid your sharp angle." I learned a lesson I'll never forget. I not only had made the storyteller uncomfortable, but also had put my friend in an embarrassing situation. How much better it would have been had I not become argumentative.

    Nine times out of ten, an argument ends with each of the contestants more firmly convinced than ever that he is absolutely right. You can't win an argument. You can't because if you lose it, you lose it; and if you win it, you lose it