Mark the writer bagged a couple? (5)
I believe the answer is:
twain
'couple?' is the definition.
(archaic term for 'two')
'mark the writer bagged a' is the wordplay.
I cannot quite understand how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is present in the answer.
'writer' could be 'i' (the person who is writing these clues) and 'i' is found within the answer.
'a' could be 'an' and 'an' is present in the remaining letters.
A single letter 'w' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for twain that I've seen before include "American author - two" , "Mark --, American author" , "Two (arch.)" , "Two of the same kind, archaically" , "Mark -, pen name of S. L. Clemens" .)