A shaft driven upward is called a raise; one that is driven downward is known as a winze.

　
英 美
  • 從下往上開(kāi)拓出來(lái)的井筒叫天井;從上往下開(kāi)拓出來(lái)的井筒叫盲井。
今日熱詞
目錄 附錄 查詞歷史
国内精品美女A∨在线播放xuan