The crown is the source of oxygen, worker of the magic of photosynthesis.

树冠是氧的来源，是神奇光合作用的制造者。

youdao

Water is not only used as a key ingredient of human subsistence but also a source of oxygen and rocket fuel necessary for the human lunar bases.

水不仅是宇航员在月球上的重要生存资源，还是月球基地所需氧气和运载火箭燃料的来源。

youdao

Conclusion leukocyte is an important source of oxygen free radical and leukocyte-depleted blood reperfusion may offer better myocardial protection.

结论白细胞是氧自由基的重要来源。提示去白细胞血再灌注，可以获得良好的心肌保护。

youdao

Being able to directly access their minds, as a reader, was like discovering an abundant, perpetually replenished, and freely available source of mental oxygen.

NEWYORKER: Olds Rocket 88, 1950

The source of the fire has still not been pinpointed, but it was widely speculated that a group of oxygen generators in the cargo hold may have caused or contributed to a blaze in the cargo hold of the DC-9.

CNN: ValuJet back in the air at last - Sept. 26, 1996