nitrogen/ˈnaɪ.trə.dʒən/名词氮(气)Nitrogen makes up about 78% of the Earth's atmosphere and is essential for the growth of plants and the production of proteins in living organisms.氮占地球大气的约78%,对于植物的生长和生物体内蛋白质的生产至关重要。想跟读,去练习