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    Plants are very important. This is because plants can make food from air, water and sunlight. Animals and man cannot make food from air, water and sunlight. Animals can get their food by eating plants and other animals. Man gets his food by eating plants and animals, too. So animals and man need plants in order to live. This is why there are so many plants around us.

    There are two kinds of plants: flowering plants and non-flowering plants. Almost all the trees around us are flowering plants. You can know some trees from their flowers and fruit. Non-flowering plants do not grow flowers. You cannot see many non-flowering plants around you.

    If you look carefully at the plants around you, you will find that there are many kinds of plants. Some plants are large and some are small. Most of them are green. Thanks to the plants around us we can live on earth.

    Zhalong is a nature reserve in Heilongjiang in northeast China. It is one of the world's most important wetlands. The reserve offers food and places to live in for wildlife. It is an ideal home for different kinds of plants, fish and birds.

    Many birds live comfortably in Zhalong Nature Reserve all year round, but some only stay there for a short time. There are many fish in the wetlands, and the birds can easily catch them for food. Zhalong Nature Reserve is an important living area for red-crowned cranes. There are not many red-crowned cranes in the world. Some of them live in Zhalong.

    Some people want to change the wetlands to make more space for farms and buildings. This means there will be less and less space for wildlife.

    More and more birds are in danger because they do not have enough living space. Many of them died. The Chinese government wants to protect these endangered* birds, and they can be safe in Zhalong.

    Every year, a lot of visitors go to Zhalong to watch birds. This year, members of our Birdwatching Club are going to study the different kinds of birds in Zhalong and the changes in their numbers.

    We do a bird count once a year. We are now inviting middle school students to help. We need more people to help us count and do something to help the birds. Many people do not understand the importance of the wetlands. We hope this information will help them understand and make them do something to protect wildlife. 

    Do you know kind words and light music can help plants grow better? Many people talk and play music to their plants. And many people try very hard to protect their plants from loud noise, strong light and bad smell. That's not all. Some people are very careful about what they say or do in front of plants. They don't talk about unhappy things and won't beat a fly near their plants.

    Do plants have feelings? Many pupils think so. Even a few scientists think that plants have feelings. But most scientists don't agree. They don't think that plants call be happy, worried, angry, loving or afraid. They don't believe that a plant's feeling can be hurt.

    Professor Cleve Backster in America did an experiment and said that plants have feelings like human beings. He published an article in a magazine in 1968. People began to pay more attention to this topic since then.

    Art, as we know, is subjective. What one person considers a priceless masterpiece others might see as nothing more than a giant black square. But there's one very specific kind of painting that almost everyone sees the same way-the kind with the" "strange" eyes that seem to follow you around the room. So what causes this optical illusion (视觉错觉) and how do artists achieve this effect?

    It turns out, for even a moderately skilled artist, this effect isn't a difficult thing to achieve, In fact, the artists need to use a little illusion of depth, making the person depicted on the canvas appears somewhat 3D on a 2D canvas, and to adjust .the gaze (凝视) of the eyes so that they would be looking at someone standing right in front of the picture.

    So what exactly is going on here in our brains that then makes it seem like the eyes follow you even if you move away from being front and center? As demonstrated by a team of researchers from Ohio State University, as you move to the side, the "near? and "far" points of the 2D image don't really change. These near and far points are defined as visible points that, if the image was 3D, would appear nearest and furthest away from the viewer at a given angle.

    The idea is simple. No matter what angle you look at a paining from, the painting itself doesn't change. You're looking at a flat surface. The key is that the near points and far points of the picture remained the same no matter the angle the picture was viewed from. When observing real surfaces in the natural environment the near and far points vary when we change viewing direction. When we observe a picture on the wall, the visual information that defines near and far points is unaffected by viewing direction. Still, we willingly accept and interpret the thing in the painting as if it were a real object.

    Thus, because the perspective, shadows, and light on the painting don't change as you move around, if the eyes in the painting would be staring directly at the observer who is standing in front of the painting, it creates something of an optical illusion in your brain so that the eyes will continue to seem to stare at you as you move to the side.

    In contrast to the eyes following you trick, if the artist tweaks the painting a bit, for example the artist adjusts the gaze of the eyes so that the eyes are looking off somewhere else instead of directly looking at a potential observer, no matter where you stand, the eyes will never seem to be looking at you.

    The technique first began popularly showing up in art around the 14th century when the artist and architect Fillipo Brunelleshi introduced the art world to the idea of "linear perspective", being painting with the idea of everything in the picture converging (聚集) on a specific point on the horizon, creating the illusion of depth. Linear perspective, combined with skilled use of light and shadow, allows artists to create masterfully realistic paintings, including sometimes of people that stare at you creepily no matter where you stand.

    How green are you？Do you know how to be green？

    We all need a healthy environment, but we produce waste every day and it does harm to our environment. Though we are young, we can still do something to help. In fact, even the simplest everyday activities can make a real difference to the environment. Here are some ideas for you.

    Reduce

    Reduce means" use less". Don't waste things. This saves money and reduces pollution and waste going into the environment. Before we buy something new, think whether it is really necessary﹣or maybe the old one will be just as good! When we do buy things, choose local products if possible, and try not to buy too many things from abroad.

    Reuse

    Reuse means" use again". Use things for as long as possible. When we buy things, make sure that they last a long time. We should look after them so that they will last, and we should repair them if we can instead of throwing them away and buying new ones. Don't use a paper cup of a paper bag. It's better to use a china cup and a lunch box because you can use them again.

    Recycle

    Recycle means" change things into something else". Though it takes energy to change something into something else, it's better than throwing things away or burning them. Find out what can be recycled in your neighborhood and take part in recycling programmes. We should also buy products made from recycled materials, such as recycled paper, to help save trees.

    So please remember these three words: reduce, reuse and recycle.