Copies I revise at times (8)
I believe the answer is:
imitates
'copies' is the definition.
(I know this)
'i revise at times' is the wordplay.
'revise' is an anagram indicator.
'at'+'times'='attimes'
'attimes' is an anagram of 'mitates'.
'i'+'mitates'='IMITATES'
(Other definitions for imitates that I've seen before include "Copies, takes off" , "Mimics or simulates" , "Apes" , "Copies, simulates" .)