Agrees those French may imprison that man (6)
I believe the answer is:
chimes
'agrees those french' is the definition.
I can't judge whether this defines the answer.
'may imprison that man' is the wordplay.
'may' becomes 'ces' (I can't justify this - if you can you should believe this answer much more).
'imprison' indicates putting letters inside.
'that man' becomes 'him' (I've seen this before).
'ces' placed around 'him' is 'CHIMES'.
Can you help me to learn more?
(Other definitions for chimes that I've seen before include "Rings" , "Bell sounds, as fitted to front door" , "Ringing sounds" , "Set of tuned bells struck with a hammer" , "Sounds made by bells" .)