单词	the flank concave
释义	the flank concave 齿形中凹
随便看	river crossing offensive operation river crossing on ice river crossing operation river-crossing operation river-crossing or sea-crossing bridges river-crossing pipeline river-crossing problem river-crossing reconnaissance river crossing regulation river-crossing road and bridge River-crossing roadway tunnel river-crossings river-crossing sector river-crossing shield tunnel river-crossing siphon river-crossing traffic river crossing tunnel river-crossing tunnel river crossover River cross-over river cross section river cross-section river cruise river current river cutoff