fine gravel

基本解释

The fine gravel or sand is then pumped down the tubing with a carrier fluid.
然后细小的砾石或砂子用携带液沿油管向下被泵入井底。
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The wind booms down the curved length of the trailer and under its roaring passage he can hear the scratching of fine gravel and sand.
风沿着拖车的轮廓呼啸着打转，他都能听到沙砾在风中发出刮擦声。
This was an adaptation to the steppes of the Central Asia, which largely consisted of a hard, rocky ground, covered with coarse sand, more like fine gravel and of stiff, parched vegetation.
这是一种适应中亚的大草原，这在很大程度上是一种坚硬，岩石地面布满粗砂，更像细砾和僵硬，口干舌燥植被，包括。

No need for an immaculate strip of lawn—a bit of fine gravel will do.
ECONOMIST: Niche sports: The running of the boules The
Filter material: layer of fine gravel used in slope stabilization structures that allows water to escape and retains soil particles.
UNESCO: L O S S A R Y