氧气筒

例句：

1. 1. The lungs need oxygen to function properly.
   肺部需要氧气才能正常运作。
2. 2. Oxygen isessential for life on Earth.
   氧气对地球上的生命至关重要。
3. 3. The scientist studied the effect ofoxygen on human health.
   这位科学家研究了氧气对人类健康的影响。