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undercourse

undercourse

 英

  • n.襯層;底層
  • 網(wǎng)絡(luò)下層

英漢解釋

n.
1.
襯層
2.
底層

例句

Revetments must be sturdy and durable, able to resist damages caused by various factors. Their undercourse must not be scoured.

對(duì)下游護(hù)坡要求堅(jiān)固耐久抵抗各種因素破壞作用保證底層