As kids, my friends and I spent a lot of time out in the woods,"The woods" was our part-time address, destination,purpose,and excuse.If I went to a friend's house and found him not at home,his mother might say, "Oh,he's out in the woods,"with a tone of airy acceptance.It's similar to the tone people sometimes use nowadays to tell me that someone I'm looking for is on the golf course or at the gym,or even "away from his desk."For us ten-year-olds,"being out in the woods" was just an excuse to do whatever we feel like for a while.

    We sometimes told ourselves that what we were doing in the woods was exploring.Exploring was a more popular idea back then than it is today.History seemed to be mostly about explorers.Our explorations,though,seemed to have less system than the historic kind: something usually came up along the way.Say we stayed in the woods, throwing rocks,shooting frogs,picking blackberries,digging in what we were briefly persuaded was an Italian burial mound.

    Often we got "lost" and had to climb a tree to find out where we were.If you read a story in which someone does that successfully,be skeptical: the topmost branches are usually too skinny to hold weight,and we could never climb high enough to see anything except other trees.There were four or five trees that we visited regularly—tall beeches,easy to climb and comfortable to sit in.

    It was in a tree,too,that our days of fooling around in the woods came to an end.By then some of us had reached seventh grade and had begun the rough ride of adolescence.In March,the month when we usually took to the woods again after winter,two friends and I set out to go exploring.We climbed a tree,and all of a sudden it occurred to all three of us at the same time that we really were rather big to be up in a tree.Soon there would be the spring dances on Friday evenings in the high school cafeteria.

    Modem zoos are different from those built fifty years ago.At that time zoos were places where people could go to see animals from many parts of the world.The animals lived in cages with iron bars（栅栏）.Although the zoo keepers took good care of them,many of the animals did not feel comfortable,and they often fell ill.

    In modern zoos,people can see animals in more natural conditions.The animals are given more freedom in larger places so that they can live as they would in nature.Even the appearance of zoos has changed.Trees and grass grow in cages,and water flows through the places the animals live in.There are few bars;instead,there is often a deep ditch（沟）,filled with water,which surrounds a space where several sorts of animals live together as they would naturally.In an American zoo,the visitors can walk through a special huge cage that is filled with trees,some small animals and many birds,and large enough for the birds to live naturally.In a zoo in New York,with the use of special nights,people can observe certain animals that are active only at night,when most zoos are dosed.Some zoos have special places for visitors to watch animals that live in the desert or under water.

    Modern zoos not only show animals to visitors,but also keep and save rare animals.For this reason,fifty years from now,the grandchildren of today's visitors will still be able to enjoy watching these animals.

    Scientists in Britain have managed to teach bumblebees(大黄蜂) to pull strings to get to food and then pass on what they have learned to others in their colony(群体)—showing a high level of intelligence despite their tiny brains.

    Researchers at Queen Mary University of London said the experiments, often used to test the intelligence of apes (猿) and birds, showed for the first time that some insects are up to the task, and can also pass skills on through several generations.

    The findings add to the evidence suggesting the ability for “culture spread” — the ability to learn and pass on knowledge and skills — may not be exclusive to humans.

    In the research, published in the journal PLOS Biology on Tuesday, the scientists were able to train 23 out of a group of 40 bees to pull strings with their legs and feet.

    The strings were attached to discs — or artificial “flowers” — containing food at their center but placed under a transparent screen. The bees, spotting the food beneath the screen, learned to pull the “flowers” out by pulling the string with their legs and feet to be able to get to it.

    From another group of bees given the chance to solve the task without any training, only two of 110 were successful.

    Another group of bees was then allowed to observe the trained bees pulling the strings, and 60 percent of them successfully learned the skill. Finally, trained bees were put in colonies, and the scientists found the technique spread successfully to a majority of the colony's worker bees.

    Lars Chittka, a Queen Mary University professor who guided the project, said the team is interested in figuring out the brain processes behind the bees' learning and teaching skills.

    When it comes to car hiring,all car hire companies require that you should have a full driving license for at least one year,some of whom may ask for two years,especially for younger drivers.

    Most car hire companies will not automatically hire out a car to someone under the age of 25 or to people over 70. But there are exceptions. Some listed companies are normally prepared to serve people of 21 and over. And some may go over the age limit and provide service for older people( aged 70 and over) providing you have no record of breaking the law and valid license, and a doctor's letter of good health.

    Now read on for some information about national companies with many bases hiring out cars to people aged 21 and older drivers.

    Mr. and Mrs. Gordon were sitting on the sand, reading their magazines. Mr. Gordon was too stingy (吝啬的) to rent (租) a chair. Their twelve-year-old daughter, Sandra, was playing at the water's edge. Suddenly a huge wave lifted Sandra up and carried her out to sea. Fortunately, a lifeguard (救生员) was on duty and he saw the wave carry Sandra away. He ran along the beach and dived into the sea. He swam quickly to where the girl was, with her head only just above the water, was shouting for help. She was very frightened. When the lifeguard reached her, she struggled with him, as drowning people often did. However, he was a skillful lifeguard and quickly took hold of her and swam with her back to the beach. By the time he reached it, Mr. and Mrs. Gordon had realized what had happened. They had run down to the water's edge. Neither of them could swim. They just stood in the shallow water, and worried about their daughter. Had the lifeguard reached her in time? Fortunately, he had. “That was quick work, young man,” Mr. Gordon said. He turned to his wife, “Give the lifeguard a dollar.” “A dollar!” Sandra cried. “Dad, how can you give him a dollar! He saved my life. I was half dead.” “Quite right, girl,”Mr. Gordon said, pleased by his daughter's awareness of the value of money. He turned to his wife again and said, “She's right. She was only half dead. Give him fifty cents.”

According to a new Agriculture Department report, U. S. forests could exacerbate global warming because they are being destroyed by natural disasters and are losing their ability to absorb planet-warming gases as they get older. The report predicts that the ability of forests to absorb carbon will start declining after 2025 and that forests could release up to 100 million metric tons of carbon a year as their emissions (排放) from decaying (腐烂的) trees go beyond their carbon absorption. Forests could become a "substantial carbon source" by 2070, the USDA report says.

The loss of carbon absorption is driven in part by natural disasters such as wildfires, tornadoes and hurricanes, which are increasing in frequency and strength as global temperatures rise. The disasters destroy forestland, destroying their ecosystem and decreasing their ability to absorb carbon, according to Lynn Riley, a senior manager of climate science at the American Forest Foundation. Aging forests also contribute. The report found that older, mature trees absorb less carbon than younger trees of the same species, and U. S. forests are rapidly aging.

This trend is likely to continue, as forests come under increasing threat from climate change and exploitation (开采). The typical tropical (热带的) forest may become a carbon source by the 2060s, according to Simon Lewis, professor in the school of geography at Leeds University. "Humans have been lucky so far, as tropical forests are cleaning up lots of our pollution, but they can't keep doing that indefinitely," he said. "We need to cut down fossil fuel emissions before the global carbon cycle starts working against us."

U. S. forests currently absorb 11 percent of U. S. carbon emissions, or 150 million metric tons of carbon a year, equal to the combined emissions from 40 coal power plants, according to the report. The loss of forests as natural carbon absorbers will require the U. S. to cut emissions more rapidly to reach net zero. "As we work to decarbonize (碳减排), forests are one of the greatest tools at our handling. If we were to lose that, it means we will contribute that much more in emissions." Riley said.