Trout, swimming around, can be instructive (5)
I believe the answer is:
tutor
'can be instructive' is the definition.
I can't tell whether this defines the answer.
'trout swimming' is the wordplay.
'swimming' indicates anagramming the letters (letters swim around into a new order).
'trout' anagrammed gives 'TUTOR'.
'around' is the link.
Can you help me to learn more?
(Other definitions for tutor that I've seen before include "Mentor" , "School" , "Teach" , "Personal teacher" , "train" .)