19.________(n.)苦难;痛苦 20.________(n.)砖;砖块 21.________(n.)水坝;堤堰 22.________(n.)轨道;足迹;痕迹 23.________(n.& vt.)援救;营救 24.________(n.)电;电流;电学 25.________(n.)灾难;灾祸 26.________(n.)矿;矿山;矿井 27.________(n.)矿工 28.________(n.)掩蔽;掩蔽处;避身处
suffering
brick
dam
track
rescue
electricity
disaster
mine
miner
shelter