单词	大小写情况
释义	大小写情况case
随便看	directional transmitter directional unit directional valency directional valve directional valve box directional wave measuring equipment directional wave spectrum directional well directional wireless direction angle direction angle (vectorial angle) direction-annexed traverse direction arm direction c. direction change relay direction character direction coefficient direction comparison protection system direction component direction control direction control circuit direction control valve direction cosine direction cosines direction coupler