Bent on doing a turn at the top, possibly (2,2)
I believe the answer is:
up to
'bent on doing' is the definition.
'up to' can be an answer for 'doing' (as in 'what are you up to?'). I'm unsure of the 'bent on' bit.
'a turn at the top possibly' is the wordplay.
'a turn' becomes 'u' (a 'U-turn' is a kind of turn).
'at' means one lot of letters go next to another.
'possibly' indicates anagramming the letters.
'top' with letters rearranged gives 'pto'.
'u'+'pto'='UP TO'
Can you help me to learn more?
(Other definitions for up to that I've seen before include "working at > till" , "As far as a certain point" , "Busy with" , "Incumbent upon" , "Engaged in doing" .)