Mend at last? (6)
I believe the answer is:
resole
'mend at last?' is the definition.
'resole' can be an answer for 'mend' (resoling is a kind of mending). I am not certain of the 'at last?' bit.
'mend at last?' is the wordplay.
'mend' becomes 'sole' (soling is a kind of mending).
'at' means one lot of letters go next to another (I've seen this in other clues).
'last?' becomes 're' (I am not sure about this - if you are sure you should believe this answer much more).
'sole' after 're' is 'RESOLE'.
Can you help me to learn more?
(Another definition for resole that I've seen is " repair boot".)