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.

    As space science develops, man has learned more and more about space. Space is not only amazing but also dangerous. While working in space, spacemen are facing danger.

    Scientists have found out that radiation(辐射) is the greatest danger to spacemen in space. When spacemen are working in space, they are in danger of radiation from the sun and other stars, which is bad for their health. Some special medicine may work a little, but there's no really helpful medicine.

    Space junk is also thought a great danger to spacemen. It's reported that there are 9,000 man-made things flying in space. About 30% of these are man-made satellites(卫星),10% are spaceships, and the rest are space junk. An explosion(爆炸) in 1996 made a cloud of 300,000 fragments(碎片), each at least 4 mm in size, and even a small piece of these knocked against a spaceship window and did some damage. Scientists are working on helpful ways to do with space junk.

    Although space is really dangerous, it interests everyone on the earth. In the near future, it may become usual for people to spend a few days in a space hotel. We may even choose to leave the earth and live in space for a few years. So we should care for space and do something to help improve the space environment.

    The days of having to carry a phone charger(充电器) everywhere could soon be over. Researchers from America have made great progress in getting energy from human motion(运动). They say smartphones could get enough power just by the motion of fingers on the screen.

    The low-cost device(装置) has already been tested in an American university. Scientists successfully showed an LED touch screen, a total of 20 LED lights and a keyboard, all with a simple touching or pressing motion and without the help of a battery.

    "What I predicted is the possibility of not having to charge your smartphone for a whole week, for example, because that energy will be produced by your motion," said one of the researchers.

    The completed device is as thin as a piece of paper. Electrical energy is created when you press it. The device used to power the LED lights is the size of a hand while the device used to power the touch screen is as small as a finger.

    The device will become more powerful when folded. Each time you fold it, the energy you create will be doubled. You can start with a large device, but when you fold it once, and again, and again. It's now much smaller, but it has more energy. It may be small enough to put in a specially made heel(脚后跟) of your shoe so it can create power each time your heel knocks the ground. The researchers are also developing technology that would send the power produced from the heel strike to an earphone.

    The unknown world's mystery

    The sea is the biggest unknown part of our world. It covers about seventy-one percent of the earth. There is still much to be discovered about this huge part of water. If the waters of the ocean could be removed, the sea floor with its wide valleys(峡谷), tail mountains and long rivers in the sea would be a special sight.

    Tourism under the deep blue sea

    From tourist submarines(潜艇) to underwater dining, undersea tourism is making a big splash.

    Tourists can now explore(探索) the world under the sea without ever getting wet.

    Tourist submarines

    The popularity of submarine tours has grown fast during these years. Now, submarine tours have been on in more than 20 places worldwide, including the waters around Okinawa and Taiwan's Green Island. The submarines carry nearly 2 million tourists each year. Large windows give passengers special views as the submarines explore colorful coral reefs and sunken ships. Most one-hour tours cost about $ 80.

    Underwater dining

    For a more fantastic experience, tourists can enjoy fine dining under the sea. In 2016 the Hilton Maldives Resort & Spa opened the world's first underwater restaurant, Ithaa. Tourists walk down a staircase into the restaurant, which rests 35 feet in the Indian Ocean. You can have a great ocean view. But this excellent view doesn't come cheap. The dinner costs about $ 400 per person. Be sure to book it early, too, The restaurant seats only 14 people.