Alpacas(羊驼) are members of the camel family, having lived in South America for thousands of years. Their fur gives the animals a teddy bear_like appearance. Alpacas are too small to be used as animals of burden but are valued only for their fur. Generally, their lifespan is around 15 to 20 years.

    Alpacas are social animals that live in family groups made up of a male, females and their young. They are gentle, elegant, curious, intelligent and observant. They are safe and pleasant to be around, moving gracefully and slowly around the field, and are therefore unlikely to run into or over anyone, even small children. Occasionally, an alpaca will spit snd kick, but the soft padded(有爪垫的) feet usually do little more than just“get your attention”.

    Because these animals are environmentally friendly and need so little grass and food, you can usually raise from two to eight alpacas on an acre of land with grass or hay. A single, 60 pound bale(大捆) of hay can generally feed a group of about 20 alpacas for one day. Alpacas also require access to plenty of fresh water to drink.

    Alpaca fur is used for making knittedd and woven(编织) items, just as sheep's wool is. These items include blankets, sweaters, hats, gloves, scarves, a wide variety of textiles(针织品) in South America, and sweaters, socks, coats and bedding in other parts of the world. The fur comes in more than 52 natural colors as classified in Peru, 12 as classified in Australia and 16 as classified in the United States.

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    In the rush to get to school, you drop a piece of toast on the floor. Do you throw it away or decide it's still OK to eat? If you're like most people, you eat it. Maybe you follow the “5-second rule”, which says foods are safe to eat if you pick them up within 5 seconds after dropping them. But you might want to think again. Scientists now say that 5 seconds is all it takes for foods to become polluted with enough bacteria to make you sick.

    Bacteria can cause many kinds of illnesses. Some kinds of bacteria can grow on food. If you eat foods on which these bacteria are growing, you can become sick.

    One of these food-borne bacteria is Salmonella. It makes 1.4 million people sick every year. Salmonella is often found in raw eggs and chicken. Cooking kills these bacteria, which is why it is so important to cook eggs, chicken, and other foods thoroughly.

    But how long does it take these bacteria to pollute food? A team of scientists in South Carolina did an experiment. First, they placed an amount of Salmonella on three surfaces: wood, tile, and carpet. They placed a piece of bread and a piece of sausage on each surface for 5, 30, or 60 seconds. After just 5 seconds, both the bread and the sausage picked up enough bacteria to make you sick.

    So, forget the 5-second rule. If your toast drops on the floor, throw it away and get another piece of clean toast. And next time, be careful not to drop it!

    Wetlands are ecosystems found in low, flat areas. Often they border ponds, rivers, lakes, and oceans. Wetlands include marshes, swamps, and bogs.

    No trees grow in a marsh, but there are lots of grassy plants. Ducks, turtles, and many different bugs (虫子) live there, too. Florida has the world's biggest freshwater marsh. The Everglades covers 4,000 square miles. The Everglades is not entirely fresh water, however. Near the sea the fresh water and salt water mix. Some plants and animals can live only in this brackish water.

    Saltwater marshes lie along the East Coast and the Gulf of Mexico. During high tide these marshes are under water. During low tide these marshes can be seen. The water rushes out, carrying bits of plants, dead animals, and minerals necessary for sea animals. Many plants and animals depend upon this ever-changing environment.

    Swamps are forested wetlands. Like marshes, they are often found near rivers or lakes and have mineral soil that drain very slowly. Unlike marshes, they have trees and bushes. Swamps have trees that grow with their roots underwater. But the trees will die if their roots stay underwater too long. Animals such as water snakes and frogs live in swamps.

    Bogs have damp, soft soil. So many dead plants have piled up that there is no longer any standing water. This rotting plant matter turns into peat (泥炭). In Ireland and Scotland peat is dried and burned to heat homes. Bog soil is useful for growing wild rice. Lots of insects live there.

    Most people do not find wetlands beautiful. But wetlands are important. Marshes and swamps store water, thus reducing the flooding a heavy rain can cause. About one-third of all of America's endangered plants and animals live in wetlands. Now laws protect some wetlands. More than a dozen wetlands in the US are refuges (保护区) and wildlife preserves.

    If you ask people to name the one person who had the greatest effect on the English language, you will get answers like "Shakespeare," "Samuel Johnson," and "Webster," but none of these men had any effect at all compared to a man who didn't even speak English-William the Conqueror.

    Before 1066, in the land we now call Great Britain lived peoples belonging to two major language groups. In the west-central region lived the Welsh, who spoke a Celtic language, and in the north lived the Scots, whose language, though not the same as Welsh, was also Celtic. In the rest of the country lived the Saxons, actually a mixture of Anglos, Saxons, and other Germanic and Nordic peoples, who spoke what we now call Anglo-Saxon (or Old English), a Germanic language. If this state of affairs had lasted, English today would be close to German.

    But this state of affairs did not last. In 1066 the Normans led by William defeated the Saxons and began their rule over England. For about a century, French became the official language of England while Old English became the language of peasants. As a result, English words of politics and the law come from French rather than German. In some cases, modem English even shows a distinction(区别)between upper-class French and lower-class Anglo-Saxon in its words. We even have different words for some foods, meat in particular, depending on whether it is still out in the fields or at home ready to be cooked, which shows the fact that the Saxon peasants were doing the farming, while the upper-class Normans were doing most of the eating.

    When Americans visit Europe for the first time, they usually find Germany more "foreign" than France because the German they see on signs and advertisements seems much more different from English than French does. Few realize that the English language is actually Germanic in its beginning and that the French influences are all the result of one man's ambition.

    All over the world people enjoy sports. Sports help to keep people healthy and happy, and to live longer.

    Many people like to watch others play games. They buy tickets or turn on their TVs to watch the games. Often they get very excited when "their" player or team wins.

    Some sports are so interesting that people everywhere go in for(参加) them. Football, for example, has spread(展开)around the world. Swimming is popular in all countries near the sea or in those with many rivers. What fun it is to jump into a pool or lake, whether in China, Egypt or Italy! And think of people in cold countries. Think how many love to skate or ski (滑雪) in Japan, Norway or Canada.

    Some sports or games go back thousands of years, like running or jumping. Chinese wushu, for example, has a very long history. But basketball and volleyball are rather new. Neither one is a hundred years old yet. People are inventing new sports or games all the time. Water-skiing is one of the newest in the family of sports.

    People from different countries may not be able to understand each other, but after a game together they often become good friends. Sports help to train(培养,训练) a person's character(性格,品格). One learns to fight hard but fight fair, to win without pride and to lose with grace(胜不骄，败不馁).

A new study looks at how pets provide important support through petting, cuddles (拥抱), and a frequent physical presence. This is especially key when people feel lonely.

The researchers interviewed 32 people aged 59 to 83 years old. Pets included dogs, cats, birds, etc. More than 90%of the people spoke about touch in the relationship with their pets. "Participants often described touch-based interactions with their pets as being comforting or relaxing in a way that contributed to their overall wellbeing," the researchers say. "For our participants, comfort is the sense of being somehow cared for by another being. "

Many people in the study spoke about how their pets just seemed to "know" when they weren't feeling well and they'd move to get physically near them. Different pets were better at providing comfort, some participants insisted. Many said cats were more relaxing companions than dogs, while others said dogs could be relaxing as long as they were "the right kind of dog". But almost all pets provided some sort of comfort to their owners when it came to touch.

Janette Young, lecturer in health sciences at the University of South Australia, and her team uncovered an interesting thing about the pet-human relationship. People in the study often spoke about how their animals demanded to be petted or seemed to take joy in the interaction. This, in turn, made the humans feel good.

The researchers suggest that pets can be "helpful in reducing touch deprivation(匮乏)" and the benefits can come from all kinds of pets. This connection can be particularly important in health care and senior care settings where patients and workers are less likely to be able to see friends and family; yet touch is important and can improve health and happiness.

Pets can also offer benefits that in some cases people can't offer. "Relationships with pets are different to those with humans," Young says. "Animals don't judge and are always with us."