Several safari camps operate as the base for this adventure, providing unique rides twice a day to explore deep into the delta. The camps have excellent horses, professional guides and lots of support workers. They have a reputation for providing a great riding experience.

              The morning ride, when the guides take you to beautiful, shallow lakes full of water lilies, tends to be more active. It is unlike any other riding experience. With rainbows forming in the splashing water around you and the sound of huge drops of water bouncing off your body and face. It is truly exciting. You are very likely to come across large wild animals, too. On horseback it is possible to get quite close to elephants, giraffes and many other animals. The sense of excitement and tension levels rise suddenly though, as does your heart rate, as you move closer to them.

              In the evening, rides are usually at a more relaxed and unhurried pace. With golden light streaming across the grassy delta and the animals coming out to eat and drink. Sedate though they are, rides at this time of day are still very impressive. As the sun's rays pass through the dust kicked up by the horses, the romance of Africa comes to life.

              Back at the camp you can kick off your boots and enjoy excellent food and wine. Looking back on your day, you will find it hard to deny that a horseback Safari is as close as you will ever come to answering the call of the wild.

Word of the Day Writing Competition

    Days are getting colder, and everyone is slowly backing to the warm comfort of their homes. It's the best opportunity to make good use of the quietness and peace of the season by taking pen and paper(or a computer) out to write.

OxfordWords of Oxford University Press(OUP) is calling all aspiring(有抱负的) authors out there to take part in our writing competition. What we're looking for are imaginative(富有想象力的) short stories—not more than 500 words—that include every Word of the Day (WOTD) from November.

    Each entry will be carefully considered by the OxfordWords team before deciding on a winner. The best storyteller will be given a year's fee to OxfordDictionaries.com, as well as ￡50 worth of OUP books, and have his or her piece published on that website.

    Before you get started, please make sure you're read our terms and conditions. Entries can be submitted(递交) through the entry form, or posted into the comment section. Closing date for the competition is 5th January 2015.

    And finally, for inspiration, have a look at the charming short story that gives us the idea for this competition, written by a fellow Oxford Dictionaries team member, and including all thirty one Words of the Day from October.

    Find out more about our Word of the Day service and sign up to receive the words via email, or on Facebook, Google, and Twitter.

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

Dear Editor,

    I am writing to you about the article in your magazine last month about youth crime. As a teenager myself I found the article rather offensive(冒犯的) as it suggested that the largest part of teenagers get into trouble with the police at some time or another. I can honestly say that I have never committed a crime(犯罪) and as far as I know, neither have any of my friends.

    I don't know where the journalist got his information from or if he did any proper research, but the way he described teenagers gave me the impression that he doesn't actually know many teenagers. Maybe when he was younger he was regularly in trouble with the police and that's where he got his ideas from. If this is true then he shouldn't judge other people from his own behaviour in the past.

    Many teenagers I know always help other people in the community, such as raising money for charity and doing voluntary work. A group of us recently spent an entire Sunday morning picking up litter in our local park. We didn't get paid for it; we just wanted to make it cleaner and safer for everyone, especially as many young children and dog walkers use the park.

    Also, as teenagers, we are far too busy studying for exams and doing homework to be "walking the streets every night, looking for trouble", as your journalist wrote in his article. I have to study after school every night during the week. I do get some free time at the weekend but I like to play football, go cycling or swimming, go to the cinema or have coffee with my friends and have a chance to talk to them. I think you will agree that there is nothing criminal about that.

    As your magazine is aimed at young readers, I think your journalists should be more careful about what they write and they should research their ideas better, or you may find that teenagers stop buying your magazine altogether.

Yours sincerely,

Daniel Browning

    The day will come when renewable energy such as wind, solar, geothermal and others replace fossil fuels as the major source of world energy. However, most analysts insist that this day will not arrive for many decades to come—certainly well past the middle of the century. Systems of fossil fuels have already been firmly set up, and it is too costly or impractical to replace the existing systems with renewables. But there are good reasons to believe that the transition (转变) to renewables will come much faster than previously thought.

    It is hardly surprising that many experts say we will see a relatively slow transition from fossil fuels to renewables, given what is known about previous energy changes of this sort. "Energy transitions take a long time," observed Vaclav Smil of the University of Manitoba in Scientific American. It took more than 50 years for coal to replace wood as the world's leading source of energy and another 50 years for oil to replace coal; the change from fossil fuels to renewables, he argued, is not likely to come any faster.

    Under ordinary circumstances, Smil's forecast would no doubt prove accurate. But these are not ordinary times. Growing concern over climate change is leading to increasingly strict controls on CO₂ and other greenhouse gas (GHG) emissions (排放), while the development in renewables technology is lowering their price and speeding their installation.

    There are, of course, many difficulties in the effective control of carbon emissions, as demonstrated by coal companies to block the introduction of new rules by the US Environmental Protection Agency. Nevertheless, it is impossible to dismiss the progress being made at the local and international levels to promote the use of renewables. The European Union (E. U), for example, is well on the way to achieving a 20% reduction in GHG emissions from 1990 levels by 2020, along with a 20% increase in the use of renewable energy.

    The transition to renewables will be faster due to dramatic improvements in the pricing and performance of such systems. As a result of the steady increases in the efficiency of wind and solar systems, together with the savings achieved through large-scale manufacture, the price of renewables is falling globally. With prices dropping this fast, solar energy is now proving competitive with fossil fuels for generating electricity in many areas.

    The change from fossil fuels to renewable energy will not come overnight, and it will not escape many setbacks. Nevertheless, renewables are likely to replace fossil fuels as the main source of electrical power well before mid-century.

    Researchers have found bees can do basic mathematics, in a discovery that deepens our understanding of the relationship between brain size and brain power. Recently, A study conducted by researchers from RMIT University in Melbourne, Australia showed that bees could perform arithmetic operations like addition and subtraction (减法).

    Solving math problems requires a complex level of involving the mental management of numbers, long-term rules and short-term working memory. The finding that even the tiny brain of a honeybee can grasp basic mathematical operations has a possible effect on the future development of Artificial Intelligence, particularly in improving rapid learning.

    RMIT's Professor Adrian Dyer said numerical (数字的) operations like addition and subtraction are complex because they require two levels of processing. “You need to be able to hold the rules around adding and subtracting in your long-term memory, while mentally using skillfully a set of given numbers in your short-term memory,” Dyer said. “On top of this, our bees also used their short-term memories to solve arithmetic problems, as they learned to recognize plus or minus as abstract concepts.”

    The findings suggest that advanced numerical cognition (认知) may be found much more widely in nature among non-human animals than previously suspected.

    “If math doesn't require a massive brain, there might also be new ways for us to include interactions of both long-term rules and working memory in designs to improve rapid AI learning of new problems,” said Dyer.

    Many species can understand the difference between quantities and use this to search for food, make decisions and solve problems. But numerical cognition, such as exact number and arithmetic operations, requires a more complex level of processing.

    Previous studies have shown some primates (灵长目动物), birds, babies and even spiders can add and/or subtract. The new research, published in Science Advances, adds bees to that list.