楼梯: stairs; staircase; stairway每: every; each; per一级: one-level; Class A; senior g ...的: 4次方是 The fourth power of 2 i ...前缘: lip; snoot; leading edge楼梯踏级的前缘: nosing一级的: first-degree; first-grade弓的前缘: leading edge of a bow; leading edge of the bow明显的前缘: sharfront羊肩的前缘: middle of neck翼的前缘: snoot纵帆的前缘: luff楼梯前缘: nosing第一级的: primary可移动的前缘: translating lip一段12级的楼梯: a staircase of 12 steps楼梯之第一级: starting step放出的前缘缝翼: extended slat可收起的前缘缝翼: retractable slat前缘区(直翅目的前翅): anterior field收起的前缘缝翼: retracted slat低一级的总成，比: chassis全翼展分布的前缘凸齿: root-to-tip extension未出露的前缘双向构造: blind frontal duplex structures国家一级的方案编制: in-country programming
