hydrogen
/ˈhaɪdrəʤən/
a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
中文释义：氢
Hydrogen is the most abundant element in the universe and a key component of stars.
氢是宇宙中最丰富的元素，也是恒星的关键组成部分。
Many researchers believe hydrogen fuel cells could replace fossil fuels in the future.
许多研究人员认为氢燃料电池未来可能取代化石燃料。