Speak of love that comes with cost? (5)
I believe the answer is:
'speak' is the definition.
(I know that orate is a more specific form of the action speak)
'love that comes with cost?' is the wordplay.
'love' becomes 'o' (love means zero in tennis).
'that comes with' is a charade indicator (letters next to each other).
'cost?' becomes 'rate' (rate is a kind of cost).
'of' acts as a link.
(Other definitions for orate that I've seen before include "Speechify" , "Lecture" , "Declaim or rant" , "Make a flowery speech" , "Speak in public" .)