英语语法分析

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。

Before the rules of diplomatic precedence were worked out in the early sixteenth century, rival ambassadors often fought for the most honourable seating position at a ceremony.

在16世纪早期外交优先规则制定之前，敌对的大使经常在仪式上争夺最尊贵的座位。

Firstly, 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.

首先，所有现有的氦供应应该被保存下来，并且只有在获得许可的情况下才能释放，医疗用途应优先于其他商业或娱乐需求。