an underground
英
美
- an art.（用在元音音素前）一
- underground adj.地下的；秘密的adv.在地下；秘密地n.地下；地铁；地道；秘密活动
- An underground bed or layer of earth, gravel, or porous stone that yields water.
地下蓄水层，砂石含水层含有水的泥、砂砾或多孔石的地下河床或地层
- An underground defensive position with a fortified projection above ground level for gun emplacements.
掩蔽壕，地堡一个地下防御工事，有一个高干地面的，用来放枪的防御射击处
- There is an underground car park near the supermarket.
这个超市附近有一个地下停车场。
- The prisoner escaped by digging an underground tunnel.
囚犯挖了一条地道逃跑了。
