Capital husband invested in modern food store (3,5)
I believe the answer is:
new delhi
'capital' is the definition.
(New Delhi is an example)
'husband invested in modern food store' is the wordplay.
'husband' becomes 'h'.
'invested in' is an insertion indicator.
'modern' becomes 'new' ('new' is associated in meaning with 'modern').
'food store' becomes 'deli' (I've seen this before).
'new'+'deli'='newdeli'
'h' inserted inside 'newdeli' is 'NEW DELHI'.
(Other definitions for new delhi that I've seen before include "Capital of India" , "big city" , "Asian capital city" , "Gambling establishments" , "Indian capital city" .)