Interpret article penned by Marx or Engels? (4)
I believe the answer is:
read
'interpret' is the definition.
(I know that interpret can be written as read)
'article penned by marx or engels?' is the wordplay.
'article' becomes 'a' (the indefinite article in English).
'penned by' means one lot of letters goes inside another (inserted letters are penned in).
'marx or engels?' becomes 'red' (red can informally mean a communist).
'a' going within 'red' is 'READ'.
(Other definitions for read that I've seen before include "Interpret writing" , "Comprehend written words" , "Lecture" , "Study (for a degree?)" , "Perused" .)