Transform a frog to achieve success (2,3)
I believe the answer is:
go far
'achieve success' is the definition.
(I've seen this before)
'transform a frog' is the wordplay.
'transform' is an anagram indicator.
'a'+'frog'='afrog'
'afrog' with letters rearranged gives 'GO FAR'.
'to' acts as a link.
(Other definitions for go far that I've seen before include "Succeed" , "Make real progress, achieve much" , "Last" , "Achieve great things" , "flourish?" .)