One friend's taken it in to make copies (8)
I believe the answer is:
imitates
'copies' is the definition.
(I know this)
'one friend's taken it in' is the wordplay.
'one' becomes 'I' (Roman numeral).
'friend's' becomes 'mates' (mate is a kind of friend).
'taken' means one lot of letters go next to another.
'in' is an insertion indicator.
'i'+'mates'='imates'
'imates' enclosing 'it' is 'IMITATES'.
'to make' acts as a link.
(Other definitions for imitates that I've seen before include "Copies, takes off" , "Mimics or simulates" , "Apes" , "Copies, simulates" .)