Tries again with a learner for practice (9)
I believe the answer is:
rehearsal
'practice' is the definition.
(rehearsal is a kind of practice)
'tries again with a learner' is the wordplay.
'tries again' becomes 'rehears' ('hears' can be a synonym for 'tries' so perhaps 'rehears' is OK for 'tries again').
'with' means one lot of letters go next to another.
'learner' becomes 'l'.
'rehears'+'a'+'l'='REHEARSAL'
'for' is the link.
(Other definitions for rehearsal that I've seen before include "show trial" , "Dummy run" , "Preparation for a show" , "preparation in house?" , "Dry run" .)