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hydrogen

英 ['ha?dr?d?(?)n] 美['ha?dr?d??n]
  • n. [化學(xué)] 氫

考試真題

Most hydrogen and oxygen atoms in water are stable, but traces of both elements are also present as heavier isotopes.

2015年12月六級(jí)真題（第二套）聽(tīng)力 Section C