Clean water is not only important for people to produce food, but necessary for our life However, many people in Asia and Africa don't have enough clean water to use The World Health Organization reports that almost 4 000 children die each day of dirty water or lack(缺乏)of water.

    Farmers use 70% - 85% 0f the world freshwater to produce food. People usually don't pay much attention to how much water industry(工业)uses, but you may be surprised to know that industry uses 59% of the water in developed countries.

    Home use takes up（占据）only 8% in the world. But as cities grow, more water will be used. The local government has to try to make people useless water. In 60% of European cities, people are saving water by using less. They even keep waste water for other use. In Australia, the government has encouraged people to collect rainwater and recycle water from showers for a second use, The US Environmental Protection Agency has made a water saving program to encourage families and businesses to check their water use and save more water. Scientists and the UN are looking for good water management as the key to solving the problem. We can all work together to protect our fresh water in our daily life.

    There are millions of different animals in the world, but some are in danger, and some may soon die out. People can never see them again. Mark and David wanted to find some of these rare animals, so they climbed mountains, crossed rivers, and walked through rainforests.

    A Bat, a Cat or a Squirrel?

    Mark and David found the aye-aye. The aye-aye has bright eyes. It has ears like a bat, a body like a cat and a tail(尾巴) like a squirrel. Some people think the aye-aye brings bad luck. They killed(杀死) many of them, and cut down a lot of trees where the aye-aye lives as well.

    A Strange Parrot

    Mark and David found the biggest parrot in the world that cannot fly. Many years ago, some animals came to the place the parrots lived in, and killed many of them. Now there are only a few left.

    Another Special Animal

    Mark and David went looking for a manatee. A manatee looks like a seal and a hippo. In some places where manatees live, the water in the river gets low. Then the manatee swims to the place where there is more water. Many get stranded(搁浅), and some are killed by other animals and people, too.

    After Mark and David returned, they made a film about these animals. They want to show the world these strange but interesting animals. They want the world to know there are not many of them left, and they all have a place in our world.

     Robots seem very new to some people, but in fact they have a long history. The first robot was made by a Greek inventor(发明家). You may often see robots in lots of movies. The robots in the movies are stronger, faster and cleverer than people. In real life, most robots are used in factories. They are used to do many dangerous, difficult or boring jobs. Some people can't look after themselves and robots are used to help them. For example, some people can't see. They use dogs to help themselves move around. These dogs are called guide dogs. Scientists are making robots to help them. In the future, robot dogs might take the place of these guide dogs.

    Robots are also used in American hospitals. At one hospital, a robot takes meals from the kitchen to the sick people's rooms. It never loses its way because it has a map of the hospital in its computer system(系统).

In the future, robots will work in space. Robots will never take the place of humans, though they can help us in a lot of different ways.

    Every day there is less and less space on Earth for rubbish. Yet every day we make more and more rubbish. What can we do? We can recycle some of our rubbish. Recycling means that the rubbish will be made into something that can be used again.

    Recycling helps Earth. And it saves space in rubbish dumps(垃圾场). Half of everything that we put into landfills could be recycled instead. In fact, most things made of paper, metal, glass and plastic can be recycled.

    Paper  can  be  broken  into  small  pieces  and  made  into  new  paper. Steel and aluminum cans(金属罐) can be melted down(熔化) and made into new cans. The same is true of glass bottles. This can be done over and over again. Recycling doesn't take as much energy as making these things the first time. So we can use less of Earth's fuel resources.

    Plastic can be melted down, too. Then it can be formed into park benches(长椅), playgrounds and so on. Some people call plastic the "wood" of the future. Things made of plastic will last about 400 years—even if they stay outside in the weather. No wood can do that!