架空

to build (a hut etc) on stilts / to install (power lines etc) overhead / (fig.) unfounded / impractical / (fig.) to make sb a mere figurehead

to support / frame / rack / framework / classifier for planes, large vehicles, radios etc

empty / air / sky / in vain

to empty / vacant / unoccupied / space / leisure / free time

aerial ropeway / cable car