Reject sentence after month (7)
I believe the answer is:
decline
'reject' is the definition.
(I know that reject is a more specific form of decline)
'sentence after month' is the wordplay.
'sentence' becomes 'line' (I can't justify this - if you can you should believe this answer much more).
'after' says to put letters next to each other.
'month' becomes 'dec' (abbreviation for December).
'line' after 'dec' is 'DECLINE'.
Can you help me to learn more?
(Other definitions for decline that I've seen before include "perform grammatical exercise" , "Say no or lose strength" , "Diminish; deteriorate" , "Downturn - turn down" , "Refuse - to take a drop" .)