Hydrogen is a one - valence element.氢是一价的元素.Valence is a sleepy little town just south of Lyon.瓦朗斯是里昂南面一座寂静的小镇。Every element tends to satisfy both its primary and secondary valence.每一元素倾向于既满足它的主价又要满足它的副价....
只有现有储户的孩子可以开立账户.Only children whose parents are existing savers may open an account.在清算银行中,储户具有举足轻重的地位.Depositors are of special importance in the clearing banks.它们为银行储户提供24小时服务.They provide bank customers with 24 - hour...