Talk of breaking up some gang (3)
I believe the answer is:
nag
'talk' is the definition.
The answer and definition can be both to do with communicating as well as being verbs in their base form.
Maybe there's an association between them I don't understand?
'of breaking up some gang' is the wordplay.
'of breaking' becomes 'an' (I can't explain this - if you can you should give a lot more credence to this answer).
'up' says the letters should be written backwards (in down clue: letters go upwards).
'some' says to take the initial letters.
The first letter of 'gang' is 'g'.
'an' reversed gives 'na'.
'na'+'g'='NAG'
Can you help me to learn more?
(Other definitions for nag that I've seen before include "Pester; old horse" , "Horse; keep scolding" , "Complaint" , "Complain continuously like old horse" , "Be persistently painful" .)