When I came to Cincinnati as an au pair (家庭打工留学生), a lot of things there were different from what I knew. My host family lived in a huge house I could only describe as a "castle"．In Germany I had lived in a small apartment together with my mom. Soon I found out that the "castle" was actually rather small in our neighborhood.

    Everybody there was very friendly and polite. They greeted you when they were walking by at least 3 feet away from you. They must not have seen a German au pair before, for most people I met asked me all kinds of questions about Germany. I enjoyed answering their various strange questions. I made a lot of friends and I started to hang out with them.

    Of course, there were a number of new things, and it took me the whole year to find them all out. I never got homesick. Perhaps it was because I did not have too many negative experiences and felt loved and welcomed there.

    However, I had undergone some painful experience back in Germany. I was frustrated by the way people would run me over and not even say "Sorry." Taking up my studies at the TU-Dresden, I felt lonely. Everybody here seemed to be withdrawn(离群的) and I missed everything I had in Cincinnati. Germany was so "cold". I found it so much harder to make new friends. After six months I got a roommate and only two good friends. I also flew back to Cincinnati several times for long periods. I felt that without those visits I was not able to make it.

    Now I am over this German culture shock. It almost took me an entire year. I am still going back and forward between Dresden and Cincinnati four times a year.

    If your job requires a lot of sitting,you could be putting your health at danger.

    The American Journal of Epidemiology（流行病学）did a study in 2010 on the connection between sitting and an individual's physical health.In the study,53,440 working men and 69,776 working women were surveyed on their time spent sitting.The subjects were all disease free when employed.The researchers identified 11,307 deaths in men and 7,923 deaths in women during the 14-year follow-up.

    The findings: Women who reported sitting for more than six hours per day had an approximately 40 higher all-cause death rate than those who reported less than three hour a day,and men had an approximately 20 higher death rate.

Well,now is a fine time to get this information.But why didn't they tell me this years ago?I would have planned on taking a more active job instead of the sedentary（坐着的）job of an editor.

    So what can you do if you have to work for a living at a job that requires a lot of sitting?Here are some ideas:

    Take frequent breaks.It is recommended that workers vary activities,change their position,and take short breaks every 20 minutes to rest muscles and increase blood circulation.Get a standing desk.Some studies have shown that working from an upright position may be better for health.The serious fitness people can even purchase a treadmill （跑步机）desk.It only goes about one mile per hour.Have a walking meeting.If your group is kind of small,going for a walk while discussing topics is a good alternative.

    Earthquakes are something that people fear. There are some places that have few or no earthquakes. Most places in the world, however, have them regularly (有规律地). Countries that have a lot of earthquakes are usually quite mountainous.

    The earthquake which was talked about most in the United States was in San Francisco in 1906. Over 700 people died in it. The strongest one in North America was in 1964. It happened in Alaska.

    Strong earthquakes are not always the ones that kill the most people. In 1755, one of the strongest earthquakes ever recorded was felt in Portugal. Around 2,000 people died.

    In 1923, a very strong earthquake hit Tokyo, the Yokohama area of Japan. One hundred and forty thousand people died. Most of them died in fires which followed the earthquake.

    One of the worst earthquakes ever was in China in 1976. It killed a large number of people. The worst earthquake ever recorded was also in China, in which about 80,000 people were killed or injured. This earthquake happened in 2008.

    Earthquakes worry people a lot. The reason is that we often do not know when they are coming. People cannot prepare for them.

    Here's a selection of festivals for tourists to the United States in summer.

San Francisco Silent Film Festival

    Films at this odd cinematic event have a variety of musical accompaniments, including piano and violin. It includes some classic silent movies. If you want to see them all, you can buy a festival pass.

May 29 to June 1; www.silent film.org

Union Street Festival

    This popular street fair stretches out over six blocks of the city, in the fashionable shopping area of Union Street. This year, there's beer, wine, biscuits tasting and more separate themes-fashion, cuisine, tech, local, craft, and health and fitness.

    June 7 to 10; www.unionstreetfestival.com

    North Beach Festival

    This is San Francisco's oldest street party, with live entertainment, delicious food and arts and crafts. Situated in the Little Italy district, known for its associations with the “Beat Generation”, festival goers are guaranteed plenty of good Italian food. There is also as the “blessing of the animals”, a San Francisco tradition which takes place at the National Shrine of Saint Francis of Assisi (610 Vallejo Street) at 2 pm on both days of the festival.

    June 14 to 16; www.sfnorthbeach.org

    Stern Grove Festival

    This is the oldest free summer arts festival of its kind in the United States. It includes a wide variety of acts, from the local symphony orchestra to well known artists such as Smokey Robinson.

    Sundays from June 22 to Aug 24; www.stemgrove.org

    Reintroducing beavers (海狸) to Britain could help clean up rivers, prevent flooding and minimise soil loss, an expert has claimed.

    Professor Richard Brazier, a researcher at the University of Exeter, said unpublished results from a trial area in Devon showed muddy water entering an area where beavers were living was three times cleaner when it left. "Our trial has shown that the beavers are able to dam our streams in a way that keeps soil in the headwaters of our catchment (流域) so it doesn't block up rivers downstream and pollute our drinking and bathing waters. If we bring beavers back it's just one tool we need to solve Britain's crisis of soil loss and agricultural pollution of waterways, but it's a useful tool," he said.

    Prof Brazier's claims were disputed by the National Farmers' Union (NFU), which warned that the reintroduction of beavers to Scotland had led to fields and forests becoming damaged. Spokesman Mark Pope said: "The knowledge of the impacts beavers have had on farmland, riverbanks and flood defences in Scotland is concerning. We await the results of the Devon trial and will analyse the outcomes then."

    Prof Brazier, an expert in Earth Surface Processes, insisted the animals could even play a useful role in preventing flooding. He told BBC News: "The public is currently paying people to build leaky dams to keep storm waters in the uplands. The beavers can do it free of charge and even build their own homes."

    However, Professor Jane Rickson, a soil specialist from Cranfield University, Bedfordshire, joined the NFU in sounding a note of caution. She agreed that in some places in the UK there was evidence of worrying soil loss, and said new policies were urgently needed. Beavers may in fact reduce the river channel and remove vegetation, exposing banks to greater erosion (侵蚀) and increasing, rather than decreasing, the risk of flooding, she warned. And she said beaver dams should be "leaky" to avoid build-ups of large volumes of water.

    Tim Berners-Lee is not the most famous inventor in the world. However, his invention has changed our lives.

    He was born in London, England in 1955.When he was a small boy, Tim was interested in playing with electrical things. He studied science at Oxford University. He made his first computer from an old television at the age of 21.

    Tim started working on early computers. At that time, they were much bigger than now. He worked in England then Switzerland. Tim was really interested in two things, computers and how the brain works. How could the brain connect so many facts so quickly? He had to work with people all over the world. They shared information about computers. It was hard to manage all the information. He answered the same questions again and again. It took a lot of time. It was even difficult for computers in the same office in Switzerland to share information. Tim also forgot things easily. Could a computer work like a brain? Could it "talk" to other computers?

    There was an Internet already but it was difficult to use. In 1989, Tim Berners-Lee invented the World Wide Web (WWW) all by himself. This had a special language that helped computers talk to each other on the Internet. When people wanted to share information with others, they used the World Wide Web. The Internet grew quickly after that.

    Tim Berners-Lee doesn't think he did anything special. He says that all of the ideas about the Internet were already there. All he did was to put them together. He says that many other people worked together to make the Internet what it is today.

    Most inventors want to become rich. But Tim gave away the World Wide Web for nothing. He now works in America. He helps people share technology and wants the Internet to be free for everyone to use. Maybe he is the most important but least famous inventor in the world today!