first aid急救firstadj.第一的；最初的adv.首先；第一n.最初；(序数词)第一First openly gay congressman dies首开同性恋众议员去世first generation Dutch resolution第一代Dutch拆分first order triangulation station一等三角点First Aid Nursing Yeomanry Service急救护士队勤务First impressions are most lasting第一个印象是令人最难忘怀的First trial composite answer print第一声画合成校正拷贝First course in mathematical logic数理逻辑初级教程first-come first-served system先到先办制First Shanghai Investments Limited第一上海投资有限公司,简称第一上海first order reduced density matrix一阶约化密度矩阵