Greg's inside at university, tardy to start studying with controls (9)
I believe the answer is:
regulates
'controls' is the definition.
(I've seen this before)
'greg's inside at university tardy to start studying' is the wordplay.
'inside' means to look at the middle letters.
'at' says to put letters next to each other.
'university' becomes 'U' (abbreviation for university).
'tardy' becomes 'late' (synonyms).
'to start' indicates taking the first letters.
The middle of 'gregs' is 'reg'.
The initial letter of 'studying' is 's'.
'reg'+'u'+'late'+'s'='REGULATES'
'with' acts as a link.
(Another definition for regulates that I've seen is " Controls or adjusts".)