Issues in Applied Linguistics

The purpose of the present paper is to bring together several studies in an emerging area of inquiry—that of second language (L2) influence on the first language (L1) in adulthood—in order to reconceptualize the findings within a unitary theoretical framework. Previous research has convincingly established that L2 may influence and even overtake L1 in childhood L2 learning (cf. Wong-Fillmore, 1991). In the present paper, evidence is presented that similar processes may take place in adult L2 learning and use, with L2 influencing L1 phonology, morphosyntax, lexis, semantics, pragmatics, rhetoric, and conceptual representations. The processes taking place in these diverse areas are brought together within a single framework as borrowing, convergence, shift, restructuring, and loss. Possible constraints on L2 influence in adulthood are proposed and theoretical implications discussed, in particular with regard to the nature of L1 competence.