Takes on (6)
'takes on' is the definition.
('adopt' can be a synonym of 'take on')
This is all the clue.
(Other definitions for adopts that I've seen before include "Assumes (an attitude)" , "Legally takes on (child)" , "Approves or accepts, a motion or accounts" , "Takes a child into one's family" , "Takes as one's own, say child" .)
'takes on' is the definition.
('assume' can be a synonym of 'take on')
This is the entire clue.
(Other definitions for assumes that I've seen before include "dons" , "Takes for granted or puts on" , "Take to be the case" , "Takes to be the case" , "Puts on; accepts" .)
'takes on' is the definition.
('tackle' can be a synonym of 'take on')
This is the entire clue.
(Another definition for tackles that I've seen is " Gets stuck into".)