In its early history, Chicago had floods frequently, especially in the spring, making the streets so muddy that people, horses, and carts got stuck. An old joke that was popular at the time went something like this: A man is stuck up to his waist in a muddy Chicago street. Asked if he needs help, he replies,“No, thanks. I've got a good horse under me.”

    The city planners decided to build an underground drainage(排水) system, but there simply wasn't enough difference between the height of the ground level and the water level. The only two options were to lower the Chicago River or raise the city.

    An engineer named Ellis Chesbrough convinced the city that it had no choice but to build the pipes above ground and then cover them with dirt. This raised the level of the city's streets by as much as 12 feet.

    This of course created a new problem: dirt practically buried the first floors of every building in Chicago. Building owners were faced with a choice: either change the first floors of their buildings into basements, and the second stories into main floors, or hoist the entire bulidings to meet the new street level. Small wood-frame buildings could be lifted fairly easily. But what about large, heavy structures like the Tremont Hotel, which was a six-story brick building?

    That's where George Pullman came in. He had developed some house-moving skills successfully. To lift a big structure like Tremont Hotel, Pullman would place thousands of jackscrews(螺旋千斤顶) beneath the building's foundation. One man was assigned to operate each section of roughly 10 jackscrews. At Pullman's signal each man turned his jackscrew the same amount at the same time, thereby raising the building slowly and evenly. Astonishingly, the Tremont Hotel stayed open during the entire operation, and many of its guests didn't even notice anything was happening.

    Some people like to say that every problem has a solution. But in Chicago's early history, every engineering solution seemed to create a new problem. Now that Chicago's waste water was draining efficiently into the Chicago River, the city's next step was to clean the polluted river.

                                                                      How I Turned to Be Optimistic

    I began to grow up that winter night when my parents and I were returning from my aunt's house, and my mother said that we might soon be leaving for America. We were on the bus then. I was crying, and some people on the bus were turning around to look at me. I remember that I could not bear the thought of never hearing again the radio program for school children to which I listened every morning.

    I do not remember myself crying for this reason again. In fact, I think I cried very little when I was saying goodbye to my friends and relatives. When we were leaving I thought about all the places I was going to see—the strange and magical places I had known only from books and pictures. The country I was leaving never to come back was hardly in my head then.

    The four years that followed taught me the importance of optimism (乐观), but the idea did not come to me at once. For the first two years in New York I was really lost-having to study in three schools as a result of family moves. I did not quite know what I was or what I should be. Mother remarried, and things became even more complex (复杂的) for me. Some time passed before my stepfather and I got used to each other. I was often sad, and saw no end to “the hard times.”

    My responsibilities in the family increased a lot since I knew English better than everyone else at home. I wrote letters, filled out forms, translated at interviews with Immigration officers, took my grandparents to the doctor and translated there, and even discussed telephone bills with company representatives.

    From my experiences I have learned one important rule: almost all common troubles finally go away! Something good is certain to happen in the end when you do not give up, and just wait a little! I believe that my life will turn out all right, even though it will not be that easy.

    Last year I lived in Chile for half a year as an exchange student with the American Field Service. Compared to most visitors, I didn't travel much. I lived with a Chilean family and had the responsibilities of any Chilean teenager. I went to school every day, in uniform. I had good days and bad days and days that I didn't understand.

    Chuquicamata, my host community, is a mining camp in the Atacama Desert. There is no disco, no shopping center, no museum or beach. Driveways must be watered daily to keep the dust down.

    When I arrived here, I was scared. It was so different from the urban middle-class America I was accustomed to. There were lost dogs on the streets, and a constant cloud of brick-colored dust came from the mine. There was no downtown, few smoothly paved(用砖石铺的) streets, and little to do for amusement. The people worked extremely hard. Rain was a rare phenomenon; earthquakes and windstorms were frequent.

    I had studied Spanish for two and a half years and was always one of the best students in my class. But in my first week in Chile I was only able to communicate and needed one person to whom I could explain my shock. I couldn't speak the thoughts in my head—and there were so many.

    Most exchange students experience this like me. Culture shock presents itself in everything from increased aggression towards the people to lack of appetite. I was required to overcome all difficulties. Being an exchange student is not easy.

    As time passed, everything changed. I began to forget words in English and to dream in Spanish and love Chilean food. I got used to not depending on expensive things for fun. Fun in Chuquicamata was being with people. And I took math, physics, chemistry, biology, Spanish, art, and philosophy.

    But the sacrifices were nothing compared to the gain. I learned how to accept as well as to succeed in another culture. I now know the world is my community and have a much deeper understanding of both myself and others.

    “To educate a girl is to educate a thousand people,” says Maimouna Samaké, a mother of six children (including five girls). “If you put one seed in the ground and rain comes, it will grow to produce many seeds.”

    Samaké, one of 2,000 residents, lives in a small village, Sounkala, in one of the world's poorest countries. Now she has a chance to see this wish come true thanks to Build On, an American non-profit organization that is building a school in her community.

    For 17 years, build On has been sending American high school students overseas to create schools in places where literacy (文化) and formal education are usually out of reach. The organization has built about 300 schools in Mali, Malawi, Nepal, Senegal, Nicaragua and Haiti. Its goal is to get young Americans in mostly urban areas to get involved in education. At the same time it can bring literacy to children and adults in poor villages in the developing world.

    Sounkala's current school only has about 70 children; mud floors, poor lighting, few desks and an absence of books mean that the school is not the most ideal learning environment. Therefore they certainly could use Build On's help.

    Samaké hasn't been to school, but she wants a better future for her five daughters, including Ramatou, 12, and Mariam, 10. “When a woman attends school, she will teach what she learns to her children,” said Ramatou, who wants to become a doctor. “She will also know how to take better care of her family.”

    Build On tries to build schools for grades one to three. If things go well over those three years, they return to help build another school for grades four to six, and then set up evening adult literacy classes.

    Ramatou and Mariam will not learn inside the walls of build On school since they are already in the sixth grade, but Samaké hopes that they will be able to attend evening classes to continue learning.

    How could we possibly think that keeping animals in cages in unnatural environments -mostly for entertainment purposes - is fair and respectful? Zoo officials say they are concerned about animals. However, most zoos remain “collections” of interesting “things” rather than protective habitats.

    Zoos teach people that it is acceptable to keep animals bored, lonely, and far from their natural homes. Zoos claim to educate people and save endangered species, but visitors leave zoos without having learned anything meaningful about the animals' natural behavior, intelligence, or beauty. Zoos keep animals in small spaces or cages, and most signs only mention the species' name, diet, and natural range.

    The animals' normal behavior is seldom noticed because zoos don't usually take care of the animals' natural needs. The animals are kept together in small spaces, with no privacy and little opportunity for mental and physical exercise. This results in unusually and self-destructive behavior called zoochosis. A worldwide study of zoos found that zoochosis is common among animals kept in small spaces or cages. Another study showed that elephants spend 22 percent of their time making repeated head movements or biting cage bars, and bears spend 30 percent of their time walking back and forth, a sign of unhappiness and pain.

    Furthermore, most animals in zoos are not endangered. Captive breeding(圈养繁殖) of endangered big cats, Asian elephants, and other species has not resulted in their being sent back to the wild. Zoos talk a lot about their captive breeding programs because they do not want people to worry about a species dying out. In fact, baby animals also attract a lot of paying customers. Haven't we seen enough competitions to name baby animals?

    Actually, we will save endangered species only if we save their habitats and put an end to the reasons people kill them. Instead of supporting zoos, we should support groups that work to protect animals' natural habitats.

    The weather affects many aspects of people's daily life. Knowing and understanding what the weather is doing is useful.

    However, the weather is also one of the most unpredictable elements in the world. Although many people watch the morning news and gather the information about the weather, this is often wrong. Whole days can be ruined by believing that the weather will be one thing, when it turns out to be another. However, owning wireless weather stations allows the owners to monitor the weather for themselves.

    Not only will these weather stations allow the owners to see what the weather is doing, but it is personalized(个性化)to them and their area. Wireless weather, stations are specifically prepared for the immediate neighborhood. Plans will be able to be made, and important decisions will no longer be ruined by bad weather.

    Although these weather stations are typically seen in homes, they can also be used very easily on farms and fishing boats. Both farmers and fishermen rely on the weather for their business and using up-to-date weather information is quite indispensable. By using the wireless weather stations, it can determine for them when to harvest crops and head back to the shore. Because of the size of the weather station, they can be moved very easily and used wherever necessary for people.

    The wireless weather stations are great for all homes, especially for areas that suffer from extreme weather conditions. The up-to-date, instant weather reports will allow a person to monitor what the weather is doing and if the bad weather is heading in their direction. Extreme weather tends to come very quickly; therefore, any information that is received is helpful.

    The weather stations are very simple to set up and are run by solar panels(太阳能板), ensuring they will work even if there is a power-cut. They are far smaller than those in previous years and give a couple of very simple read-outs for the owner. They are easy to use and fascinating to understand.