Where the witch had to finish a piece of work (5)
I believe the answer is:
endor
'where the witch had' is the definition.
I don't know anything about this answer so I cannot judge whether this works.
'finish a piece of work' is the wordplay.
I cannot quite see how this works, but
'finish' could be 'end' (synonyms) and 'end' is present in the answer.
'piece' could be 'r' (abbreviation for Rook) and 'r' is found in the answer.
'of' could be 'o' and 'o' is found in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
'to' is the link.
Can you help me to learn more?
(Another definition for endor that I've seen is " Witch of - - (OT)".)