Change into, for the bend (4)
I believe the answer is:
turn
I believe this is a double definition.
'change into' is the first definition.
(thesaurus)
'the bend' is the second definition.
('turn' can be a synonym of 'bend')
'for' acts as a link.
(Other definitions for turn that I've seen before include "Rotate for a performer's act" , "Bend, move round" , "Transform - revolution" , "Go - short walk" , "Distinctive expression" .)