Unmanned post offices meant millions of letters went unsorted.邮局无人工作意味着许多信件无人分拣。an unmanned Mars mission无人火星探测Scientists say these unmanned flights can make important and exciting discoveries.科学家们说这次无人驾驶的太空飞行能够获得令人兴奋的重大发...
Unmanned post offices meant millions of letters went unsorted.邮局无人工作意味着许多信件无人分拣。...a special unmanned spacecraft.一架特别的无人驾驶飞行器The fare from the last unmanned station is probably less than a pound...从上一个无人站过来的费用可能还不到1镑。......