Soon computers and other machines will be able to remember you by looking at your eyes! The programme works because everyone's eyes are different. So in the future you won't have to remember a number when you want to use a machine or take money out of a bank. You'll just have to look at the machine and it will be able to tell who you are.
The eye-recognition programme is already being tested in shops and banks in the USA, Britain, Spain, Italy and Turkey. Soon, this technology will take the place of all other ways of finding out who people are.
However, scientists are working on other systems. Machines will soon be able to know you from the shape of your face or hand or even your smell! We already have machines that can tell who you are from your voice or the mark made by your finger.
Eye-recognition is better than other kinds because your eyes don't change as you get older, or get dirty like hands or fingers. And even twins have different eyes, so the programme can be up to 94％ correct, depending on how good the technology is. Some programmes may only be right  51％ of the time. In Britain, it was found that 91％ of people who had tried it said that they liked the idea of eye-recognition. In the future your computer will be looking you in the eye. So smile!

Where does the wind come from? What makes the wind move(移动) all the time? Scientists tell us that it is the sun. That makes air move, and makes it blow(吹). When the sun shines on the earth, it makes the earth hot. Then the earth makes the air hot. When the air becomes hotter, it also becomes lighter(更轻). The light air goes up. Cool air comes into take the place of（代替） the hot air. The hot light air goes up higher and higher until it becomes cool. Then it comes down again, and then the earth makes it hot again, and it has to go up. When the air move, it has wind.

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    Everyone knows that exercise is important. It makes your heart and body strong. But you need to know the following.

*Get your body ready!

    Before you do any exercise, be sure to warm up for at least five minutes. During warming up, you should stretch(伸展) all parts of your body.

*Exercise enough, but not too much.

    It's good to exercise twice each week. Thirty minutes each time is enough. Try all kinds of things until you find one, two or even three sports that are right for you.

*Exercise at fitness centres.

    There is a lot of equipment(设备) at fitness centres. The equipment will help exercise your arms, legs and other parts of your body to make you fit. Some people buy equipment. But it is very expensive.

*Stop playing when you are hurt!

    If you get hurt when you are doing exercise, don't play again until you are well.

*Don't get thirsty!

    Drink a lot of water when you are playing sports because it is easy to become thirsty.

    Have you ever had trouble sleeping in a new place?

    Lots of people do. And now researchers from Brown University in Rhode Island think they know why. They found that one-half of the brain "remains more awake" than the other half when people are trying to sleep in a new place.

The sleep findings were reported in Current Biology by Brown University. In their report, the researchers said many people report they have a harder time sleeping the first night at a hotel or other places outside their home. They call it "first-night influence". "In Japan they say, 'If you change your bed, you can't sleep,'" said Yuka Sasaki, one of the report's writers. "You don't sleep very well in a new place. We all know about it."

    The researchers measured brain waves (测量脑波) for 35 volunteers over two nights in a laboratory. The two nights were a week apart (间隔). They found during the first night the left half of the brain was more active than the right half. This was during the first deep-sleep period, the researchers said.

    Sasaki said a lot of questions remain.

    Researchers did not keep measuring brain waves all night long. So, they don't know if the left half keeps "watch" all night, or whether it "works in shifts (轮换) with the right half later in the night". They also do not know why the brain activity, at least during the first period of deep sleep, is always on the left half.

    For some, this research may be calming. It is good to know that our brain is "looking out for us" in a new place. But it may not help with sleep. That brain activity, at least according to this new research, makes it harder to get the sleep people need to wake up well rested in the morning.

    RIVER DOLPHIN RUNNING OUT OF TIME

The Yangtze dolphin is the only kind of dolphin that lives in freshwater all its life. Scientists say that the finless freshwater dolphin that has lived in the Yangtze River for over 20 million years, will die out in 15 years. It's in danger of disappearing forever.

    Dangers:

    Dredging(挖掘) of their habitat

    Heavy boat traffic in the Yangtze River

    Insecticide(杀虫剂) and mercury(汞)

    We all cry for water when we are thirsty. But do you know, in very hot, dry weather, plants also make very low sounds as if they are crying for help?

    You see, in a plant's stem there are several hundred "water pipes" that bring water from soil all the way up to the leaves. When the ground turns dry, it becomes harder and harder for plants to do this.

    In very hot days, plants have to get any water that they can get.

    Scientists Robot Winter has found out that when plants can get no water, their "water pipes" snap(发出声音). When that happens, the whole plant vibrates(颤动) a little.

    Robot knows that healthy, well-watered plants are quiet. He also knows that dry plants are many insects' favorites and they often attack(袭击) them. How do the insects know which are healthy plants and which are not? Robot thinks that the insects may hear the plants "crying" and they may come to kill them.