There are many colors in nature. But do you think that a color has weight? I think you'll say 6/no". But I'm afraid you are wrong. If you don't believe it, you may do a small experiment(实验).

  First, put two objects with the same weight into two boxes. Then cover the boxes.Third, wrap(包裹) one box with a red piece of paper, the other one with a white piece of paper. OK. Now hold the boxes with your hand one by one. It is certain that you will think the red one is a little heavier.

 Why do you think so? A scientist found that different colors have different weights in man's mind. That is to say, every color has its own weight in our mind.

 The scientist told us that colors also have smell. Can you smell the color? Of course not. Then why did the scientist say S07 That is because every color stands for (代表) a kind of light with a certain wavelength,(波长). It reaches our brain through sense organs

 According to this discovery, scientists say that people accept the colors they like, and refuse the colors they hate. So your body and mind will be healthy by using the colors you like. Or you'll be nervous or even get ill.  For example (例如) ,  you like blue and hate red.  If you stay in a room with red windows, wallpaper and furniture（家具) for two hours, you'll feel you have been there for four hours. But if the room is blue, you'll feel you have been there for only an hour.  And, if a person walks out of a blue room and into a red room, his temperature will rise.That means our body temperature will change with different colors.

Recent research from the Pew Internet Project suggests that 90% of Americans aged from 12 to 17 use the Internet, and 51% of those teens use social networks. However, there are many possible problems with social networking sites and the teenagers who use them.

Apart from the social advantages, social networking sites can be used to record school research, develop artistic talents and experiment with other forms of subject creation. They provide a way to communicate with others who share the same interests and to get helpful advice on ongoing projects.
Along with these advantages come some dangers. For example, most social networking sites are open to all, especially MySpace, which is the most popular social network among teens in America. It means that they could be put in unpleasant and frightening situations.
A greater danger is that teens may become objects of the people with secret purposes. The secrecy of some social networking sites makes it easy for dangerous people to find young teens and invite them into dangerous conversations. It's easy for them to pretend as teens and draw children into dangerous real-world communication as well. Then further hurt might be on its way.
Another danger is identity stealing, which can happen when teens share too much information about their names, dates of birth and locations.
Therefore, it's very important to make sure teens are safe when they use social networks.
Many of the same rules that work for online chat work for these sites:
※Don't use your real name.
※ Don't give out personal information to people you don't know. A last name and a town are enough for a bad guy to find where you are.
※ Don't believe that people are who they say to be.
※ Immediately end any communication that makes you uncomfortable and report it to a parent.
Only if you are sure of your safety, can you enjoy the fun brought by social networking. Besides, trying to deal with all problems on your own can lead to terrible results. Remember, asking your parents or school officials for help doesn't mean you are unable to do anything but wiser than many others.

    Anyone who has had a long-term illness knows that recovering at home can be lonely. This is can be especially true of children. They may feel isolated（孤立的）from their friends and classmates. Now, a small robot may help children who are recovering from a long-term illness in the hospital or at home. The robot takes their place at school. Through the robot, the children can hear their teachers and friends. They can also take part in classroom activities from wherever they are recovering – whether at home or from a hospital bed.

    The robot is called AV1.It is created by a company called “No Isolation”. AV1 goes to school for a child who is at home while recovering from a long-term illness. And the child's school friends must help. They carry the robot between classes and place the robot on the child's desk.

    Dolva, one co-funder （创始人）of No Isolation, explains how the robot AV1 works. She says, “the robot sits at the child's desk in the classroom and the child at home uses a tablet（平板电脑）or a phone to start it, control its movement with touch, and talk through it. So the robot becomes the eyes, the ears and the voice of the child at school.” The robot is equipped with speakers, microphones and cameras that make communicating easy. Moreover，The AVI was designed to be tough. It is water-resistant(防水) and can take a fall from a desk without damage. Inside AV1 is a small computer connected to a 4G network. AV1 is large and looks like a human for a reason. Dolva thinks this is important because the robot is expected to be a friend to the children.

    The robot just became available to the public. Hopefully AV1 will help some children feel less lonely while they are absent from class.

    American researchers have successfully developed a way to clean waste water without chemicals. The technique uses green plants. The tests were carried out at waste treatment centre. The scientists put plants in narrow containers inside a glass building. One end of each container was a little higher than the other end. Waste water was directed down the containers through the plants' thick roots as we expected. The roots absorbed the waste in the water and used it for food. At the same time the plants produced natural gas. The gas could be collected and sold as fuel(燃料).

    Four places in Florida are already using green plants to clean their waste water.

    Do you still get free plastic bags from the supermarkets? Things have changed.

    China has banned(禁止) free plastic bags at shops and supermarkets, and people have to pay for using plastic bags. The rule started on 1st June. It came because our country tried to make litter less. Making super­thin(超薄的)plastic bags has also been banned.

    The Chinese once used about 3 billion plastic shopping bags a day, and they have caused pollution of the environment. The bags have become a main cause of plastic pollution because they are easy to break and people throw them away here and there. So the Chinese people are encouraged to bring their own bags for shopping.

    What kind of shopping bag is the best to bring? Some students in Chongqing have a good idea. They make their own shopping bags. They use old clothes to make cloth bags(布袋), and send them to their parents as presents. They also ask their parents and friends to use cloth bags instead of plastic ones. They think it is their duty to protect the environment.

People love walking through a giant puzzle. In a corn maze(玉米迷宫), they can follow miles of paths and run into lots of dead ends before they finally find their way out. The corn maze has been growing for almost 30 years. 

Simple corn mazes began appearing in the 1980s. In 1993, the first big corn maze created for the public to enjoy was made in Annville Pennsylvania, by Don Frantz and Adrian Fischer. Then, in a corntield as big as two and a half football fields, Mr. Frantz created "The Amazing Maize Maze"with the help of his family and friends. When it was done, almost two miles of pathways snaked through the cornfield. Since then, thousands of corn mazes have been created around the world.

For many farmers, a corn maze means a boost(激增) of extra income. During the opening weekend, about 6, 000 visitors came to get lost in Mr. Frantz's maze. Charging only $5 per person, he earned almost $32, 000in two weeks.

Brett Herbst is also a maze designer. In 1999 he set a world record for the world's largest corn maze, an image of the solar system with nine planets in it. He now has a business called The Maize, which has designed more than 4, 000 mazes around the world. "Corn mazes help people connectwith their roots, "he says. "People are so far removed from farm life that they are drawn to something real, something organic. "

Today, a great number of people enjoy seeking fun in a corn maze. Mr. Herbst says, "When we see families on the farm having fun, we know that they are making memories that will last a lifetime. "