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    There is a lake near a forest in Sweden. The water in the lake is very clear and everything is quiet and still. On the far side of the water is some farmland and further away, across the field, is an old church built on a hill. It has just stopped raining. The brook(小溪) flowing into the lake is full and there is still some half-melted(半融化的) snow from last winter on the ground.

    The reason the water is so clear, and everything is so quiet and still, is that most of the plant and animal life in and around the lake is dead. There are no birds because all the fish and insects, which the birds need for food, have disappeared. Many trees in the forest are losing their leaves and bark (树皮), and are sick and dying. Others were blown down by the high winds of last winter. A farmer is working in a field planting something, but unless he plants a stronger kind of seed this year, the crop will be between 25 to 40 percent lower than a few years ago. The stones of the old church tower are turning to powder and unless the tower is repaired soon, it will fall down.

    All the death and destruction(破坏) in this place is caused by the smoke coming out of factories and poisonous gases from cars and trucks. And yet this silent lake is hundreds of meters aways from the nearest factory and highway.

    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 neces sary 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 can 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 or 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 the recycling program.We should also buy products made from recycled materials,such as recycled paper, to help save trees.

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

    The idea of being able to walk on water has long interested humans greatly. Sadly, biological facts prevent us ever accomplishing such a thing without artificial aid-we simply weigh too much, and all our mass pushes down through our relatively small feet, resulting in a lot of pressure that makes us sink.

    However, several types of animals can walk on water. One of the most interesting is the common basilisk Basilicus basilicus, a lizard(蜥蜴) native to Central and South America. It can run across water for a distance of several meters, avoiding getting wet by rapidly hitting the water's surface with its feet. The lizard will take as many as 20 steps per second to keep moving forward. For humans to do this, we'd need huge feet that we could bring up to our ears in order to create adequate "hitting."

    But fortunately there is an alternative: cornflour. By adding enough of this common thickening agent to water (and it does take a tot), you can create a "non-Newtonian" liquid that doesn't behave like normal water. Now, if the surface of the water is hit hard enough, particles(粒子) in the water group together for a moment to make the surface hard. Move quickly enough and put enough force into each step, and you really can walk across the surface of an adequately thick liquid of cornflour.

    Fun though all this may sound, it's still rather messy and better read about in theory than carried out in practice. If you must do it, then keep the water wings handy in case you start to sink and take a shower afterward!

    When I was a little girl, my family lived in the countryside. There was a beautiful river near my home. The water was clean and cool. I liked to go fishing there with my mother. We would catch fish, look for clams(蛤)and play in the water. There were also a lot of birds near the river. We would spend all day watching the birds.

    Now my family live in the city. Last Sunday, my daughter asked me to take her to see the river I was always talking about. "I want to go fishing there so much with you and Grandma," she said.

    When we went to the river, we only saw a factory and a mountain of waste. My mother was surprised, my daughter was disappointed, and I was sad. The river was my best friend. I grew up with it. Now there are no fish in it, and the birds have gone too. I hear them crying for help. But what can I do?