Leave the ranks and walk briskly (4,3)
I believe the answer is:
step out
'leave' is the definition.
(I know that step out is a more specific form of the action leave)
'ranks and walk briskly' is the wordplay.
I cannot quite understand how this works, but
'walk' could be 'step' (I've seen this in another clue) and 'step' is found in the answer.
The remaining letters 'out' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'the' is the link.
Can you help me to learn more?
(Other definitions for step out that I've seen before include "Move apace" , "Leave briefly" , "Have a busy social life" , "Be busy socially" .)