Told to keep back at the edge of the road (4)
I believe the answer is:
kerb
'edge of the road' is the definition.
'kerb' can be an answer for 'edge' (kerb is a kind of edge). I'm not certain of the 'of the road' bit.
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for kerb that I've seen before include "stone by the way" , "Pavement edge" , "Roadside" , "Side of road" , "on the borderline?" .)