It all began with a stop at a red light.

    Kevin Salwen was driving his 14-year-old daughter,Hannah,back from a sleepover in 2006.While waiting at a traffic light,they saw a black Mercedes Coupe on one side and a homeless man begging for food on the other.

    "Dad,if that man had a less nice car,that man there could have a meal," Hannah protested.The light changed and they drove on,but Hannah was too young to be reasonable.She pestered（纠缠）her parents about inequity,insisting that she wanted to do something.

    "What do you want to do?" her mom responded. "Sell our house?"

    Warning!Never suggest a grand gesture to an idealistic teenager.Hannah seized upon the idea of selling the luxurious family home and donating half the proceeds（收入）to charity,while using the other half to buy a more modest replacement home.

    Eventually,that's what the family did.The project—crazy,impetuous（鲁莽的）and absolutely inspiring—is written down in detail in a book by father and daughter scheduled to be published next month: The Power of Half.It's a book that,frankly,I'd be nervous about leaving around where my own teenage kids might find it.An impressionable child reads this,and the next thing you know your whole family is out on the street.

    At a time of enormous needs in Haiti and elsewhere,when so many Americans are trying to help Haitians by sending everything from text messages to shoes,the Salwens offer an example of a family that came together to make a difference—for themselves as much as the people they were trying to help.In a column a week ago,it described neurological（神经生物学的）evidence from brain scans that unselfishness lights up parts of the brain normally associated with more primary satisfaction.The Salwens' experience confirms the selfish pleasures of selflessness.

    Mr.Salwen and his wife,Joan,had always assumed that their kids would be better bigger house.But after they downsized,there was much less space to retreat to,so the family members spent more time around each other.A smaller house unexpectedly turned out to be a more family-friendly house.

    Recently, I experienced a wonderful lesson in how little things still mean a lot. My brother, mother and I live in a very rural district of Hawaii. Our farm is at least a dozen miles from the most basic of services. Therefore, I take weekly trips to COSTCO to get supplies. About a month ago, I finished loading up the car and was about to leave, when a piece of paper caught my eye. I picked it up and read it carefully.

    It was a receipt(收据) from the State Motor Vehicle Division, recording the owner's payment of her Vehicle's Registration fees. At first I thought that I could find the owner. So I waited there for about an hour. Although the receipt had been borne (由……携带) on the wind, where in the busy, crowded parking lot would I find the owner? I looked over the receipt for contact or any personal data, perhaps a license tag(牌照)or telephone number. I checked the date, the fees paid, noted the name of the owner and pocketed the paper. I concluded that the best and easiest step to take was to put the receipt in an envelope and send it to the owner first the next morning.

    By the end of the week, I received a beautiful thank-you letter from a very grateful and happy woman containing a handwritten message and a gift card. In the letter, the woman explained how the wind snatched(夺去) her receipt from a pocket in her car's passenger door. She had searched everywhere for quite some time before giving up.

    It felt great to know I'd helped someone avoid a loss by doing something that at first glance(一瞥) seemed little or even unimportant.

    On the eve of our daughters' weddings, I gave both of them what I considered to be excellent marital advice: never leave your husband unsupervised （无人监督的） with pruning shears （修枝剪）.

    If only I had taken my own advice. I recently let my guard down. Thirty﹣some years of marriage can do that to a woman. Give a man pruning shears and electric trimmers （电动修剪器） and he will give new meaning to "armed and dangerous."

One day earlier this year, my husband said that the crab apple tree was dead.

    "Why do you think it is dead?" I asked.

    "Look at it. There's not a leaf on it."

    "There's not a leaf on anything. It's March," I said.

    "It looked sick last fall and with this bitter winter we had, I'm convinced it's dead."

    The truth is he's never liked the crabapple. Sure, it has beautiful blooms in the spring, but then it gets a disease, the leaves curl, and it drops those little apples that sit on the driveway.

    Each passing week he pronounced the tree dead. Eventually I began to believe him. Though he agreed it would be a regrettable loss, there was a twinkle in his eye. He armed himself a couple of weeks ago and began trimming. A branch here, a branch there, a small limb, then a large limb. I watched and then decided to check the wood on some of the branches closer to the trunk. I broke one off and saw green.

    The crabapple was not dead. It just hadn't had time to leaf out. The tree was now falling to one side, but it was not dead. I would have told him so, but he had moved on to a maple. Once the man starts, he can't stop. One trim leads to another.

    "Please, stop!" I called.

    He smiled and nodded, but he couldn't hear because he had started the hedge （树篱） trimmers and was getting ready to fix a line of hedges.

    Zip （飕飕声）, zip, zip.

    "What do you think?" he shouted.

    "It's supposed to be a privacy hedge; now all that will be private are our ankles."

    He started the trimmers again.

    "Stop!" I called, "Come back!"

    "Why?" he shouted.

    "You're in the neighbor's yard."

    Although it's great to spend vacations seeing the world with family, friends, or a lover, traveling alone can also be completely incredible. A solo adventure has the potential to be life-changing. Here are some reasons you should travel alone at least once.

    If you enjoy meeting new friends, here's your chance; you will likely find some when traveling alone, Since you won't be focused on talking to anyone you know, you'll be more likely to strike up conversations with strangers. Meeting people from different backgrounds opens our minds, expands our world, and can inspire us a lot. You may meet some amazing locals or other adventurers like yourself; either way you're bound to make some new friends during your journey.

    A trip alone can ignite your creativity. Spending time alone with an open mind can be exactly what you need for your imagination to soar. Your enthusiasm and passion for life may sky-rocket from your awesome adventure.

    When traveling with a partner or a group, every idea can be bounced off someone else. When you travel alone, you will learn to be decisive; you will be making every decision alone. From where to eat, to what time to wake up, to what sights to see, and which airline to use, traveling solo forces you to rely on yours truly. As you realize you can make good choices without help from others, you will likely trust your instincts more, and this new found self-assurance and confidence will be helpful in many areas of your life.

The World's Largest Libraries

    British Library (United Kingdom, London)

    The British Library was created by Act of Parliament in 1972; previously, the library had been part of the British Museum, where the famous circular reading room had accommodated researchers including Karl Marx, who worked on 'Das Kapital' there, as well as Oscar Wide and Mahatma Gandhi. The British Library is now housed in a new building in St. Pancras, London, where its treasures include two Gutenberg bibles, the Lindisfarne Gospels and one of Leonardo da Vmci's notebooks.

    Library of Congress (United States, Washington, D. C.)

    Founded in 1800 with the private collection of Thomas Jefferson, the Library of Congress is in effect the USA's National Library. It receives two copies of everything published in the United States. The Library of Congress wag burned by the British Army in 1812, and severely damaged by fire again in 1851. The collection includes many rare books, drawings and two Stradivarius violins.

    New York Public Library

    The New York Public Library developed gradually in the nineteenth century from the merger and acquisition (收购兼并) of a number of public and private collections; it has many branches in different districts of New York City. It remains a structure which combines public and private finance and governance. Treasures held at the library include a Gutenberg Bible.

    Russian State Library (Moscow)

    Founded in 1862 as the Moscow public library and museum, this collection became the State Library in 1925. In consequence it receives copies of all Russian publications, and also holds large collections of maps, journals, music scores and recordings. Its possessions include the Archangel Gospel, a codex in the Slavonic language dating from 1092.

    The huge T­rex (霸王龙) bends over a large triceratops (三角龙) lying on his side below. With its mouth open wide, the T­rex looks ready to kill the triceratops with a final bite to the triceratops's neck. The display will be found at the National Museum of Natural History.

    The museum has sought a huge T­rex skeleton (骨架) for many years. Before, it used a model of one. But museum director Kirk Johnson says that was never good enough. "It's been kind of deeply embarrassing to be the national museum and NOT have a T­rex," he said. The T­rex display is now the centerpiece of the museum's newest show, which will be available to the public on July 15.

    That T­rex, named Sue, was found in South Dakota. Officials at the museum built a special area for the skeleton. It includes a gift store of all things related to Sue. Sue even has her own Twitter account and a media presentation of her life story.

    In modern times, movies like "Jurassic Park (侏罗纪公园)" have helped grow dinosaur interest for a new generation of young fans. But such movies describe the T­rexes as mostly huge, stupid and dangerous animals, which are true threat in the fighting: quick, intelligent and aggressive hunters in groups.