Two articles supporting chap in South American country (6)
I believe the answer is:
guyana
'south american country' is the definition.
(country in South America)
'two articles supporting chap' is the wordplay.
'two articles' can mean two replacements for 'article'.
'article' becomes 'an' (indefinite article).
'article' becomes 'a' (the indefinite article in English).
'supporting' is a charade indicator (letters next to each other) (in a down clue, some letters go below others).
'chap' becomes 'guy' ().
'an'+'a'='ana'
'ana' put after 'guy' is 'GUYANA'.
'in' is the link.
(Other definitions for guyana that I've seen before include "South American republic" , "Country E. of Venezuela" , "Cricket-playing country" , "South American country, a British colony until 1966" , "Country of S. America" .)