Large income, more expensive wine, extra tuition (8,7)
I believe the answer is:
learning support
'extra tuition' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'large income more expensive wine' is the wordplay.
I cannot really see how this works, but
'large' could be 'l' (eg in clothes sizes) and 'l' is located in the answer.
'income' could be 'earnings' (earnings is a kind of income) and 'earnings' is located in the answer.
'wine' could be 'port' (port wine is a kind of wine) and 'port' is present in the answer.
'more expensive' could be 'up' (I've seen this in other clues) and 'up' is present in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?