（ ）waste of time!

（ ）waste of time! a waste of time “Bai Feili”means（ ） A.a waste of time B.waste of time C.a wa It's a waste of time exactly! A waste of time and effort 用“a waste of time”造句. it was a waste of time and It is only a waste of time 怎么用a waste of time造句 a waste of time 怎么造句? a waste of time 咋个造句 It`s a waste of time.（改为感叹句）求解答?