tunnel excavation隧: tunnel; underground pass roa ...不: a block of wood挖: dig; excavate; scoop导洞开挖: pilot drive道洞开挖法: pilot method of excavation下载手机词典可随时随地查词查翻译关注微信公众号：chachacidian，回复:隧不洞开挖，即可在微信中查询翻译
