单词	hark back to sth
释义	hark back to sth 🌏回到sth
随便看	operational site operational situation operational situation picture operational skill operational skills operational slant range operational slope operational software operational space operational spare operational specification Operational Specific Intelligence Collection operationalspeed operational speed operation al speed operational speed of a computer Operational speed of train operational sphericity operational stability operational staff operational staff study operational stage operational standard operational standard cost operational standardization