Hurry ( Informal ) (4,2,2)
(Other definitions for chop-chop that I've seen before include "Quickly!" , "Get a move on!" , "Hurry up!" .)
(Other definitions for step on it that I've seen before include "improve rate of advance" , "Go for speed" , "Hurry! - set point (anag)" , "How might one kill an ant" , "So join the escalator" .)