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来源:雅诚德英语网
All existing supplies of helium ought to be conserved and released only by permit, with medical uses receiving precedence over other commercial or recreational demands.
现有的所有氦供给应该被保存下来,并且只有在获得许可的情况下才能释放,医疗用途优先于其他商业或娱乐需求。