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     When people think of important resources, they think of oil, gas and coal.  Many people in water-rich regions think that water can never be used up because the rain keeps falling. 

     There are around 7 billion people on Earth.   Less than a century ago, there were just 1 billion humans. There are more of us being born and most of us are living longer. We are using up far more of the world's resources at a faster rate than ever before. 

     Water is the key to all life on Earth.   The UN has stated that each person needs around 135 liters of water a day for a good quality of life. At the moment, the average amount of water we use is far larger in much of the world 

     If how we use water is not managed well enough, we could face increasing shortages in the future. This will lead to terrible conflict (冲突) over scarce water resources.  

     There needs to be greater cooperation between the water-rich countries and the water-poor countries.   If water is managed as a global resource and a basic human right, not as something for profits, then the supply can be managed.