In this paper I explore changes in varieties of North American French resulting from a) loss in productivity of the re- prefix in French; and b) availability of the English particle back in contact varieties. We see that addition of back to speakers’ repertoires is dependent upon social factors while its integration into the grammar of vernacular varieties may involve both semantic and syntactic reanalysis of the English lexical item. Under the right social conditions, back becomes a French aspectual adverb.