Guy and I go to the French capital (6)
I believe the answer is:
manila
'capital' is the definition.
(Manila is an example)
'guy and i go to the french' is the wordplay.
'guy' becomes 'man' (I've seen this before).
'and' means one lot of letters go next to another.
'go to' says to put letters next to each other.
'the french' becomes 'la'.
'man'+'i'+'la'='MANILA'
(Other definitions for manila that I've seen before include "Animal found in Philippines" , "Nail Ma up with strong paper" , "Far East capital" , "Strong brown paper; cigar, cheroot" , "Adulterated, tainted" .)