• 头一炉

first one第一个firstadj.第一的；最初的adv.首先；第一n.最初；(序数词)第一first-person shooting第一人称射击first principle of odes颂的本原first difference series一阶差分数列first-gear engagement头档齿轮啮合first personal pronouns第一人称first put on trial sale先行试销First Day on the Campus大学校园first overtone CO laser泛频CO激光器first-mover advantage先发优势first come first served先到者先接受服务原则