0 the activity of managing aircraft from the ground as they take off, fly, and land, or the people who do this -- 空中交通管制(人員)
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
再长的路,一步步也能走完,再短的路,不迈开双脚也无法到达。