○  中学生英语演讲——the great race  ○

ner and locally made. major auto manufacturers and oil companies have often been seen as part of the problem (we can\'t buy what they refuse to make). but, from their perspective, they can\'t sell what we don\'t want to buy.. to them, it is our penchant for gas-guzzling sports utility vehicles that is dangerous, wasteful and suddenly unpatriotic.
　　hydrogen sources and supply infrastructure
　　hydrogen is abundant, but there are supply problems. hydrogen is almost never found in its pure form. it is already combined with other elements to form water or any number of organic compounds. to get pure hydrogen, you have to separate it from something. in the case of water, the process is called electrolysis. in hydrocarbon fuels, it is called reformation.
　　although hydrogen has been successfully reformed from all major fuels, industrial applications for hydrogen today generally rely on reforming it from natural gas. this technique can at best be a short-term solution if the goal is to be independent from fossil fuels. other sources of hydrogen include glucose, sodium borohydride and even bacterial composting. not all of these will make the cut. renewability is a key issue. the money, time and effort to turn gtas filling stations, hydrogen filling stations is mind and budget-boggling.
　　the other problem is supply infrastructure. the money, time and effort to turn gas filling stations. there is considerable mental energy going into solving these problems, but they will not be so;ved quickly or cheaply. at least i believe.

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