Agreement, default rules, and grammatical viruses

Certain constructions of prestige English, including nominative Case in coordination and plural agreement in expletive constructions, pose difficulties for speakers of English uncharacteristic of normal linguistic constructions. Assuming the Minimalist Program, these linguistically deviant constructions (Emonds 1986) form a structurally coherent group exhibiting signature characteristics including lexical specificity and insensitivity to certain phrasal constituents. Such constructions are argued to be the product of grammar-external rules called grammatical viruses. Virus theory offers an explanation within minimalist assumptions of how editing toward such prestige constructions takes place in derivation and of why such constructions are difficult to acquire and control