Downlen.唐尔downadv.向下prep.沿着 ... 而下adj.向下的；消沉的；无礼的n.绒毛；汗毛v.击倒；打败；吞下；被抑制down-up control上行控制down landing gear起落架down warped basin土动陷盆地down at the heelsadj.穿得把后跟磨掉了(邋遢的；处境穷困的)down hand welding[化] 平焊down-the-hole潜孔down-conversion下变频down-slope flow下坡气流down-modulation下行性调节downlock cylinder下位锁动作筒