名词短语
中文翻译：氧气浓度的易燃极限
同义词：
['oxygen concentration', 'oxygen content', 'oxygen level']
例句：
-
1. The oxygen concentrationin the air is crucial for fire safety.
空气中的氧气浓度对防火安全至关重要。
-
2.The oxygen content in the soil is essential for plant growth.
土壤中的氧气含量对植物生长至关重要。
-
3. The oxygen level in the atmosphere has been increasing due to human activities.
由于人类活动，大气中的氧气水平一直在增加。