The human brain is divided into two sides, or hemispheres, called the right brain and the left brain. The two hemispheres work together, but each one specializes in certain ways of thinking.

    Each side has its own way of using information to help us think, understand, and process informa—tion.The left side of the brain controls language. It is more verbal and logical. It names things and puts them into groups. It uses rules and likes ideas to be clear, logical, and orderly. It is best at speech, reading, writing, and math. You use this side of the brain when you memorize spelling and grammar rules or when you do a math problem.

    The right side of the brain is more visual and creative. It specializes in using information it receives from the senses of sight, sound, smell, touch, and taste. This side of the brain likes to dream and experiment. It controls your appreciation of music, color, and art. You use this side when you draw a picture or listen to music.Although we all use both sides of our brains, one side is usually stronger or dominant. Some people are more “left—brained,” and others are more “right—brained”. Our dominant side influ—ences the kinds of jobs and hobbies we have. Politicians, artists, architects, and musicians depend on their right brains. Accountants, engineers, doctors, and lawyers usually rely on their left brains.

    Like most of her friends, Georgie Sanderson has 24-houpa-day access(使用权) to technology through her mobile phone, iPod Touch and home computer. But the 15-year-old girl says she is too busy to spend her days on Facebook. She only uses it once or twice a day. "The 10th grade is busy, and I have to work hard. Even when I'm not studying, I have better things to do with my time, such as being outside or spending time with my friends," she says. Georgie has a part-time job. She watches TV for a while in the afternoon and she helps with the housework.

    Georgie's words prove the findings of a new report. According to the report, teenagers today are not completely dominated(支配) by technology, although they have been into a digital(数字) world. They spend most of their time on their homework, TV, part-time jobs, hobbies, sports, friendship or reading instead of playing or chatting on the computer. But the report also finds that mobile phones are important to teenagers. 95 percent of 18 year-olds have got one mobile phone, and 82 percent sleep with their mobile phones on and beside them all night.

    For Georgie, sleep is more important than texting others. Georgie is also careful about the use of IT. She says, "Social media is helpful, but it is so distracting(使人分心的). I only use it when I do need to use it."

    Every year on April 22, People all over the world celebrate Earth Day. It is a time to work to keep our earth clean. People plan projects to clean up the land, air and water.

    U.S. Senator Gaylord Nelson first thought of the idea for Earth Day in 1962 when he saw polluted rivers and cities with smoke. He needed to get support from Americans to clean up the earth. Finally, on April 22, 1970, 20 million Americans celebrated the first Earth Day! Now many countries around the world celebrate it, and you can, too.

    How can you celebrate Earth Day? Here are a few ideas:

    Join a clean-up project-Clean up your street or a favorite beach.

    Save energy-Turn off the lights when you leave a room, and use public transportation.

    Use less water.

    Reduce(减少)/ Reuse/ Recycle ― Practice the three Rs: First, reduce how much you use. Then reuse or recycle what you can.

    You can make a difference on Earth Day and every day!

    SoFi is a special "fish". It is 47 centimeters long. It is all white. It has a small round head. What kind of fish is it? Actually, SoFi is a soft robotic fish. Scientists from MIT made it look like a real fish. They want to use it to study sea animals when the ocean environment changes.

    SoFi's skin is made of a kind of rubber. It's soft. The robotic fish's head is 3D printed. There is a camera in its nose and it can take photos and videos underwater. SoFi can swim among real fish. It is quiet. It doesn't scare other fish. It can also turn left and right, and even change its speed.

    Although SoFi is not the first lifelike robotic fish, it is the most advanced of its kind, according to MIT scientists. Many other countries have also made robotic fish, including the UK and China. Scientists said these robotic fish can easily get close to other fish. And other fish can even interact (互动) with them.

    What is the best way to help control air pollution in our towns and cities? Choose public transportation instead of private cars, or reduce the total amount of cars on the street. These can be useful. But here is a more creative way—write a poem.

    "I write in praise of air. I was six or five, when a magician opened my fist(拳头), and I held in my hand the whole of the sky."

    Professor Tony Ryan (the science expert) and Professor Simon Armitage(the words expert), from the University of Sheffield, UK, came up with the idea.

    But in fact, the poem is not the key part. It is the poster that the poem was written on that plays the biggest part. The poster is 10 meters by 20 meters. It is coated with nanoparticles(纳米粒) of titanium dioxide (二氧化钛). It can absorb the waste from around 20 cars each day if you put it by a busy road. The poster is now displayed on one of the University of Sheffield's buildings.

    It doesn't get rid of all the pollutants from traffic, but it will eat up things called nitrogen oxides (氧化氮). These play a part in breathing problems, including asthma(哮喘).

    The technology is cheap. "It would add less than £100 to the cost of a poster and would turn advertisements into catalysts(催化剂) in more ways than one," Ryan told the BBC.

    He's also working on another idea, which is to add the nanoparticles to washing powder, so that your clothes soak up these poisons while you walk along. And you wouldn't be able to see or feel anything different.

    Imagine you are taking a walk on the beautiful beach. Just then, your feet step over something and you hear a crack (噼啪声) —an empty plastic bottle. Things like this are happening more often because of sea rubbish.

    Studies show that 80%of all the waste is from the land. The waste is mainly plastics (塑料制品) which are really hard to degrade (降解). So the rubbish will remain there for a long time. Some of the pollution is caused accidentally. For example, about 10,000 product-filled boxes are lost at sea every year from business ships. Sometimes people just throw things into the water from boats or land. Many large rubbish areas are formed in the North Pacific Ocean.

    Thankfully, the situation isn't ignored (忽视). Groups like the National Oceanic and Atmospheric Association (NOAA) are taking action to help clean the sea. Since 2006, 76 projects have cleared out 3,814 metric tons (公吨) of rubbish from the sea. Methods of rubbish cleaning include using machines to remove (移除) the waste away from the surface of sea water. Besides, special nets are set by the mouths of rivers to stop the rubbish before it reaches the sea. If everyone does his part, sea rubbish seems like a problem that can be solved.