Water runs downhill from mountaintops to streams to rivers to oceans. But downhill isn’t the only way that water moves .A new study measures how water travels from country to country for human consumption. This flow isn’t the type we usually think about .These scientists looked at the water used to grow and make the products which get shipped from nation to nation as imports or exports. They call this a flow of“virtual water（虚拟水）”. We typically think about water as the liquid that flows from a tap. However,92％of the water used by people goes into growing crops，according to water researcher Arjen Hoekstra. He recently studied the hidden travels of virtual water used in products made from things like crops and meats .These products are shipped around the world. For example．consider a sugary soft drink. Hoekstra estimated that to produce one half-liter of the drink requires between 170 and 310litersofthewater—about 95％—is used to grow and process the ingredients(原料).Another 4％goes into the packaging and labeling. In Hoekstra’s calculation, when one country produces a half-liter of soda and sells it abroad，it exports as much virtual water as would fill a large refrigerator． According to Hoekstra’s new report，dry countries like Israel and Kuwait，both in the Middle East, get the majority of their virtual water from other countries，through imported products. More surprisingly, some wetter countries，like the Netherlands and the United Kingdom, also get the majority of their virtual water from other places. That means that most of the water used to grow or produce the products and food consumed in those countries came from other countries. In the United States most of the virtual water used comes from American sources .In China even less of the water associated with its products 小题1:What is the best title for the passage?
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