Proposal not to go on? (5)
I believe the answer is:
offer
This clue might be a double definition.
'proposal not' is the first definition.
(I know that proposal of marriage is a type of offer)
'go on?' is the second definition.
'offer' can be an answer for 'go' (thesaurus). I am unsure of the 'on?' bit.
'to' is the link.
Can you help me to learn more?
(Other definitions for offer that I've seen before include "Present for acceptance or rejection" , "Propose; make available" , "Proposition" , "Expression of willingness to pay or give" , "Attempt" .)