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    You don't have to be a weatherman to tell people about the weather. If you notice the animals, the sky and the world around, you can predict weather on your own.

    Examine the moon or sun, but do not look at the sun directl or it will hurt your eyes seriously. If you see a ring around the sun or moon, then warm weather follows. A golden ring around the moon warns us that a storm is on the way. A watery yellow sunset is a sign that rain may be near. Feel the direction of the wind. A wind blowing from the east shows that a storm will probably happen. A wind from the west means a sunny day. Monitor the clouds. There are three things about clouds you should look for: movement, color, and change. As a rule , the higher the clouds, the better the weather.  And the lower the clouds , the worse the weather will be.

    The rainbow has a message, too. If you see the sun in the east and a rainbow in the west, the rain may be coming your way. If the sun is in the west and the rainbow is in the east, the rain will be moving away from you. Look at your shoes as you walk through the grass in the morning. If the grass is wet with dew (露珠), then you can expect dry weather. But if the grass is dry, then it will be wise of you to take your umbrella.

    Scientists in Britain and the United States have made a new kind of enzyme(酵素) that eats plastics(塑料). With its help, plastics can be turned into smaller parts and go away quickly.

    Scientists believe that, in the future, it could solve the problem of plastic pollution.

    The enzyme is able to break down PET, a form of plastic. PET was first made in the 1940s and is now widely used to make plastic bottles. It can remain in the environment for many years and pollute large areas of land and water. So it has always been a headache to deal with the waste from PET and other plastics.

    The researchers made the discovery(发 现) while examining the structure of a natural enzyme in Japan. They found that the natural enzyme was helping to break down PET plastics. So, they

decided to make small changes to the enzyme by adding some amino acids(氨基酸). It made the natural enzyme's plastic-eating abilities work faster and better.

    John McGeehan, one of the lead researchers, said, "We've made an improved enzyme. It's better than the naturl one. And we are trying to make more improvements to it." He went on."

    The enzyme is not harmful to humans or animals, and it is friendly to the environment. So we are considering putting it into wider use."

    The team is now trying to make the enzyme break down PET in large quantities(大量的). "We'll see that the plastic pollution may be stopped with this technology. However, there is still a long way to go," John McGeehan added.

    When throwing away rubbish, do you know which Bin it should go in? Have you ever noticed the differently-colored Bins on the street?

    Some of you might not be able to answer this question. However, it's actually quite important to know how to sort your waste. Not knowing how to sort waste can make it harder to save energy and protect the environment.

    If you don't sort your waste, all of it will go to a landfill and Be Buried(埋) together. These landfills can take up large areas of ground that could have Been used for planting trees or Crops. The electronic waste you throw away, such as Batteries, Can pollute the soil and groundwater. Other pieces of waste, like the metal part of a pen, can be used to make other things if they are properly recycled.

    With this in mind, many Cities in China have Been running waste-sorting Campaigns (活动)in recent years. For example, Shanghai announced in July that within three years, all of its residents(居民)should sort their waste into four groups wet, recyclable, harmful and dry.

   "Wet" waste is also known as household waste." They are things you don't want but that pigs can eat," Guangzhou Daily explained. Paper, metal, glass and other things that Can Be reused are recyclable waste.

    Harmful waste includes things like medicine, Batteries and fluorescent Bulbs. Finally, any waste that's not wet, recyclable or harmful will go in the" dry waste" bin.

    Many other Chinese Cities, including Shenzhen, plan to use this method to sort their garbage. Now that you know this, perhaps you can do your part to protect the environment and encourage others to sort their waste.

    Is there intelligent (有智力的) life on other planets? For years, scientists said "no" or "we don't know". But today this is changing. Seth Shostak and Alexandra Barnett are astronomers (天文学家). They believe intelligent life exists (存在) somewhere in the universe. They also think we will soon contact these beings (人；生物).

    Why do Shostak and Barnett think intelligent life exists on other planets? The first reason is time. Scientists believe the universe is about 12 billion years old. "This is long enough for other planets to have intelligent life," say Shostak and Barnett. The second reason is size—the universe is huge. "Tools like the Hubble Telescope (哈勃望远镜) have shown that there are at least 100 billion galaxies," says Shostak. "And our galaxy, the Milky Way, has at least 100 billion stars. Some planets going around these stars might be similar to Earth."

    In the past, it was hard to look for signs of intelligent life in the universe. But now, powerful telescopes (高倍望远镜) allow scientists to discover smaller planets. These planets might have intelligent life.

    Have beings from space already visited Earth? "Probably not," says Shostak. However, intelligent beings may contact us in other way, such as radio signals (信号). In fact, they may be trying to communicate with us now, but we don't have the right tools to receive their messages. However, this is changing. By 2025, we could make contact with other life forms in our universe and we might help each other.