短語(yǔ)詞組短語(yǔ)fine gravel [地質(zhì)]細(xì)礫;細(xì)礫石gravel beds 礫石層的gravel mill 卵石磨clay gravel 粘土礫石層;粘土礫石crushed gravel 壓碎礫石;碎礫石river gravel 河礫石;河礫gravel packing 礫石充填;礫石過(guò)濾層gravel shoulder 礫石路肩filled gravel 填礫gravel layer 礫石層；疏水石sandy gravel 砂礫石，砂質(zhì)礫石gravel pack 礫石過(guò)濾層gravel road 碎石路sand gravel 砂礫石 返回 gravel