Student expresses disapproval at pair of sweethearts (5)
I believe the answer is:
tutee
'student' is the definition.
(someone being tutored)
'disapproval at pair of sweethearts' is the wordplay.
I cannot quite understand how this works, but
'disapproval' could be 'tut' (I have seen 'Express disapproval' mean 'tut' so perhaps 'disapproval' could also mean 'tut') and 'tut' is present in the answer.
'sweethearts' could be 'ee' (two E's - E is the 'heart' of 'swEet') and 'ee' is present in the answer.
No letters remain.
This explanation may well be incorrect...
'expresses' is the link.
Can you help me to learn more?
(Other definitions for tutee that I've seen before include "Student, pupil" , "One learns from a personal teacher" .)