More changes to great city (4)
I believe the answer is:
rome
'great city' is the definition.
'Rome' can be an answer for 'city' (Rome is an example). I am not sure about the 'great' bit.
'more changes' is the wordplay.
'changes' indicates anagramming the letters.
'more' is an anagram of 'ROME'.
'to' is the link.
Can you help me to learn more?
(Other definitions for rome that I've seen before include "All roads lead to it" , "Italian city" , "European capital" , "church" , "Italian capital (where one Ac died)" .)