Single male, I will pursue love with love song from Napoli (1,4,3)
I believe the answer is:
o sole mio
'song from napoli' is the definition.
'o sole mio' can be an answer for 'song' (I've seen this before). I am not sure about the 'from napoli' bit.
'single male i will pursue love with love' is the wordplay.
I cannot really see how this works, but
'single' could be 'sole' (similar in meaning) and 'sole' is found within the answer.
'male' could be 'm' (common abbreviation) and 'm' is found within the answer.
'i' is found in the answer.
'love' could be 'o' (love means zero in tennis) and 'o' is found in the answer.
A single letter 'o' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for o sole mio that I've seen before include "Neapolitan song" , "Italian original of Presley's It's Now or Never" , "Air" , "Italian tune" , "It's Now or Never used this Italian song" .)