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.

    My heroes are the Singapore Women's Everest Team．In 2009，they became the first all-women team to climb Mount Everest．The team of six young women trained for seven years before they climbed the mountain．It was difficult for them to train because Singapore doesn't have any snow or any mountains．But they didn't stop，and in the end they made it．They Worked hard every day for their dream so I really admire them．

——Lance Reed, 16, from Britain

    My mum，Mary Evans，is a real hero．I have a very big family, with two brothers and three sisters．My mum works very hard every day to look after us, and she is very busy．She always makes time for everyone and she always listens to me if I have a problem．I really respect my mum because she always looks after my family and makes sure we have everything we need．

——Mark Sterling，l7，from America

    I admire the Salwen family from Atlanta，USA．In 2006, they made a very unusual choice．They decided to sell their house and give half of the money to charity(慈善)．They moved into a smaller house and gave $800,000 to charities in Ghana. I really respect them because they gave their money to people in need．

——William Kloster, 17, from Canada

    I really admire Steve Jobs, the former CEO of Apple．He invented a new kind of technology．Apple technology is very intelligent(智能的)．The products that he made are also really beautiful．Steve Jobs created a successful business in IT．I was very sad when he died in October 2011．I respect him because he changed the way people use technology all over the world．

——Richard Hale, 18，from Australia

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    Put your car keys away and forget about your travel pass — it's time to do a bit of walking.

    National Walking Month is organized every May by Living Streets, an organization that campaigns for the rights and the needs of pedestrians — indeed, the organization was previously known as the Pedestrians' Association. The association's aim is to make streets safe, attractive and enjoyable spaces for people to live, work, shop and play. By putting people (rather than vehicles) first, Living Streets wants to create streets and spaces where people feel happier, healthier and more sociable.

    The annual campaign gives participants a great opportunity to experience the many virtues（优点）of walking. These include the physical health benefits of becoming fitter; the environmental advantages of not using vehicles（车辆）; the joy of local discoveries seeing more of your local area on foot; the enjoyment of walking with other people, whether family, friends or work colleagues and finally the stress relief that comes from walking—walking can clear your head.

    Walk to School Week, 19 to 24 May, is part of the month's activities and its aim is to encourage parents to send children to school on foot, rather than take them in the car or let them use public transport. The movement was started in 1995 with only five participating schools and now two decades later, more than one million children take part.

    Similarly, there is Walk to Work Week, 12 to 16 May, where grown-ups are encouraged to walk. In the morning, getting off the bus a stop early or parking a few streets away is a good way to add more steps to the daily total. And during the working day, rather than having lunch at the desks or in the canteen, take a walk and get some fresh air. Walk home with your workmates and chat away about everything under the sun but work!

    The Humane Society of Utah,a non-profit organization,is the largest shelter in the state because it takes every animal that can be lawfully accepted.The shelter employed photographer Guinevere Shuster,from New York,who came up with a creative way to find new homes for the dogs.She took lively photos for them.

The 31-year-old created sets of four pictures showing the playful and serious sides of each animal.Guinevere Shuster tried her best to show these dogs the way they'd really look if you allowed them into your life.She said,"I'm always trying to imagine better ways to make the poor animals attractive to the public.The photos show their great personalities and are a much better way than presenting them as the sad dogs waiting to be taken home.I'm lucky because I get to connect the two things I love most,animals and photography."

Guinevere says she finds it easy to work with dogs.She said,"It's just me and the dog in the office so they can pay their attention to the photo-taking.I use a lot of treats and some funny noises I've learned to get the dogs' attention. A fun method is to throw treats at the dogs-it's useful for getting unusual looks from them."

    Since starting the project,a number of dogs have been taken home by dog lovers after they saw Guinevere's pictures on the Humane Society of Utah's Facebook page.In the last three years,she has photographed more than 4,000 animals.This year,the shelter has placed nearly 9,000 homeless pets into their permanent homes.

    If you are studying at school, do be a polite and clever student! There is no excuse for not doing your assignments. If you can't come to school, you should call your teacher or your classmate ask about homework. It is your responsibility to find out what homework you have missed. It is not the teacher's job to remind you of the missed assignments.

    You must not be absent on a test day. If you are seriously ill, call and let the teacher know you will not be there for the test. If your teacher allows a make-up test, you should take the test, again within one or two days after you return to class. Serious illness is the only reason for missing a test.

    Be on time! It is impolite to be late. Also, it bothers other students. If you must come in late, be sure to do it quietly. Have your books and papers out of your bag before you come into the classroom. Then go to your seat and sit down quietly. In the USA, it is not necessary to knock before you enter the classroom. Most teachers will give you a low grade if you are often late.

    In America, you should call your teacher by his or her last name instead of “teacher”. Also you should use Mr, Miss, Ms or Mrs before the last name (such as Mrs Smith or Mr Jones). The teacher will tell you the title that he or she likes. It is impolite in the USA to eat, drink or chew gum during class. Don't do these until the break. Also, removing your shoes in the classroom is not polite.

The problem of food borne metal contamination (污染) has taken on new urgency, thanks in part to a 2021 US Congressional Report detailing high levels of metals found in baby food pulled off grocery shelves. More recently, high levels of lead (铅) were discovered in children's fruit puree pouches. Now, two new studies provide information on the correlation between exposure to heavy metals in food and the risk of cancers and other serious health risks.

Food crops can absorb heavy metals from contaminated soil, air, and water. As a result, traces of dangerous heavy metals — lead, arsenic (砷) and cadmium (镉) — are found in common foods from rice and cereals to nuts and vegetables. Felicia Wu, Michigan State University food scientist, is leading several investigations to gain a better understanding of the health risks of heavy metal exposure.

In the studies, Wu and her colleague, gathered data on the dietary intake of each metal from various sources such as food and water samples and existing studies and reports. There searchers analysand the data to determine the strength of the association between dietary exposure and bad health effects. Both cancer and non-cancer health effects were considered.

Lead is a poisonous metal commonly found in old paint, water pipes, and contaminated soil. Food sources of lead include root vegetables like beets. In the study, lead showed moderate (中度的) to high risk scores for causing lung, kidney, bladder, stomach, and brain cancers. It also showed moderate to high scores for non-cancer risks.

Their initial estimates suggest that every year, more than 6, 000 additional cases of bladder and lung cancers and over 7, 000 cases of skin cancers can be attributed (归因于) to the consumption of inorganic arsenic in the United States. The researchers also found that certain food products can be associated with higher cancer risk than others. These include rice, wheat, and leafy green vegetables.