oxycel

例句：

1. 1. Oxygen is essential for the survival of all living things.
   氧气对所有生物的生存至关重要。
2. 2. The scientist used a special device to extract oxygen from the air.
   这位科学家使用了一种特殊的装置从空气中提取氧气。
3. 3.Oxygen is released into the atmosphere during combustion.
   燃烧过程中会释放氧气到大气中。