The word“day” has two meanings. When we talk about the number of days in a year,  we are using “day” to mean 24 hours. But when we talk about day and night,  we are using“day” to mean the time between sunrise and sunset. Since the earth looks like a ball,  the sun can shine on only half of it at a time. Always one half of the earth is having day and the other half night. A place is moved from day into night and from night into day over and over by the spinning（旋转）of the earth. At the equator（赤道）day and night are sometimes the same length（长度）. They are each twelve hours long. The sun rises at 6 o'clock in the morning and sets at 6 o'clock in the evening. For six months the North Pole is tilted（倾斜）toward the sun. In those months the Northern Hemisphere（半球）gets more hours of sunlight than the Southern Hemisphere. Days are longer than nights. South of the equator nights are longer than days. For the other six months the North Pole is tilted away from the sun. Then the Southern Hemisphere gets more sunlight. Days are longer than nights. North of the equator nights are longer than days. Winter is the season of long nights. Summer is the season of long days.

● Try to stay away from places with too much noise. If you have to go, wear earplugs. A pair of good earplugs can cut the noise by 30 decibels. ● When swimming, remember to put earplugs into your ears to stop water from getting in.

● Never put anything sharp into your ears. If you think you have too much earwax, ask your mum or dad to help you clean it out. Keep these things in mind! Then you won't be saying “WHAT? WHAT?" when you are older.

      In Barnes London Wetland Centre, you can enjoy a large number of wild birds and wild animals. Adults' fare is ￡7.95, and children's fare is ￡4.50. But if holding a London pass, you can have free admission(入场)。

London Wetland Centre is thought to be the European City's best place to contact wild animals. London Wetland Centre is the UK's most worthy of showing off, and the most exciting wildlife projects, including(包括) 43 hectares of grassland, as well as pools.

Barnes wetlands are located in the Thames. This award-winning centre always interest many scientists. There are many different kinds of animals, including the cormorant(鸬鹚), the kingfisher(翠鸟) and the endangered water vole(河鼠).

In London Wetland Centre there are a large number of different habitats. When visiting the centre, visitors can watch movies through the video to learn more about wetlands and the knowledge of biological species(物种).

      For children, London Wetland Centre is a good choice to learn a lot about the knowledge of nature.

      There are many other interesting places about wildlife. If you are interested in wildlife, Why not go to London Zoo, Regent Park or River Thames downstream to experience the world's most beautiful gardens? Holders of London Passes can visit them freely.

    A city without cars would be very strange, right? But Venice is such a city.

    Venice is in the northeast of Italy. It wasn't built on land, like Beijing or Shanghai, but on more than 110 islands. Seawater is everywhere around the city.

    Even so, travel isn't difficult. The waterways have always been the best way to get around. There are 117 waterways and more than 400 bridges that can guide you where you want to go.  People in Venice move from place to place by boat.

    Water makes the city special, but it is also a big problem. Sometimes tourists will have such strange experiences. One moment they walk across the Rialto Bridge, and there's nothing special. But when they come back to the bridge an hour later, it's underwater and everyone is wearing rain shoes.

    Once, people used too much underground water. This made the city get lower little by little. Now the city has gone down by 23 centimeters. Another problem is the rising seawater. The temperature has risen over the years. This has made the ice of the Arctic Ocean (北冰洋) melt( 融化). Every year, high waters hit the city in autumn and winter. When a lot of water comes, more than half of the city is underwater.

    Scientists are trying different ways to stop the city from getting even lower. The Italian government has asked some of Italy's biggest companies to build the MOST project, which was planned to be build under the seawater to stop the rising water. Anyway, this project is helping solve the problem.

    Are you shy? If you are, you are not alone. In fact, close to 50 percent of people are shy. Almost 80 percent of people feel shy at some point in their lives. These days, shyness is becoming more and more common. Now, scientists are trying to understand shyness. They have some interesting ideas about why people are shy.

    Is it possible to be born shy? Many scientists say yes. They say 15 to 20 percent of babies behave shyly. These babies are a little quieter and more watchful than other babies. Interestingly, these shy babies usually have shy parents. As a result, scientists think that some shyness is genetic.

    Family size might cause people to be shy as well. Scientists at Harvard University studied shy children. They found that 66 percent of them had older brothers and sisters. The scientists said that these children were often bullied(欺侮) by their older brothers and sisters. As a result, they became shy. At the same time, children with no brothers and sisters may be shy as well. Growing up alone, they often play by themselves. They are not able to learn the same social skills as children from big families.

    You may also be shy because of where you were born. When scientists studied shyness in different countries, they found surprising differences. In Japan, most people said they were shy. But in Israel, only one of three people said so. What explains the difference? One scientist says the Japanese and Israelis have different opinions of failure. In Japan, when people do not succeed, they feel bad about themselves. They blame (责备) themselves for their failure. In Israel, the opposite is true. Israelis often blame failure on outside reasons, such as family, teachers, friends, or bad luck. In Israel, freedom of opinion and risk-taking are strongly supported. This may be why Israelis worry less about failure and are less shy.

    For shy people, it can be difficult to make friends, speak in class, and even get a good job. But scientists say you can get over your shyness. They suggest trying new things and practicing conversation. And don't forget—if you are shy, you are not the only one.