a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth\\\'s crust
造句
用作名詞(n.)
Water contains hydrogen and oxygen. 水含有氫和氧。
Hydrogen and oxygen are gases. 氫和氧是氣體。
Plants can absorb carbon dioxide and release oxygen. 植物可以吸收二氧化碳釋放氧氣。
Mars is too dry and poor in oxygen. 火星上面過于干燥，并且缺乏氧氣。