Subject taught in commercial premises at last (4,9)
I believe the answer is:
home economics
'subject' is the definition.
(home economics is a kind of subject)
'taught in commercial premises at last' is the wordplay.
'taught in' becomes 'home' ('he's in' can mean 'he's home'. I am not sure about the 'taught' bit.).
'commercial' becomes 'economic' (I've seen this in another clue).
'at last' suggests the final letters.
The final letter of 'premises' is 's'.
'home'+'economic'+'s'='HOME ECONOMICS'
Can you help me to learn more?
(Other definitions for home economics that I've seen before include "Domestic science" , "Cookery studies etc" , "Study of cookery and household management" , "1 [GCSE]" .)