Drops a message saying we should get a move on (4,2)
I believe the answer is:
lets go
'drops a message saying we' is the definition.
I can't tell whether this defines the answer.
'should get a move on' is the wordplay.
'should' becomes 's' (this could be a standard abbreviation of which I'm unaware).
'get' indicates putting letters inside.
'a move on' becomes 'letgo' (I've seen this in another clue).
's' going into 'letgo' is 'LETS GO'.
Can you help me to learn more?
(Other definitions for lets go that I've seen before include "Come on then, we're off!" , "Liberates" , "Order to leave" , "Releases from one's grip" , "fires" .)