Studies in Language 33:2 (2009), 366–395. doi 10.1075/sl.33.2.06mat issn 0378–4177 / e-issn 1569–9978 © John Benjamins Publishing Company Contact-induced grammaticalization Evidence from bilingual acquisition* Stephen Matthews and Virginia Yip University of Hong Kong / Chinese University of Hong Kong It is widely acknowledged that developments in bilingual individuals parallel, and ultimately underlie, those taking place in the course of contact-induced change. In this paper we address the poorly understood relationship between the individual and community-level processes, focusing on the process of grammati- calization in circumstances of language contact and the corresponding develop- mental processes in bilingual acquisition. he phenomena chosen for discussion are drawn from Singapore Colloquial English (SCE) and from the Hong Kong Bilingual Corpus (Yip & Matthews 2000, 2007). Parallel developments in SCE and bilingual acquisition are analysed as cases of contact-induced grammatical- ization as deined by Heine and Kuteva (2003; 2005), with some modiications. he emergence of already as a marker of aspect presents a case of ‘ordinary’ contact-induced grammaticalization, while the development of grammatical functions of give represents a case of replica grammaticalization. One implica- tion of these indings is that bilingual irst language acquisition is a possible route for substrate inluence, both in general and speciically in the development of contact languages such as pidgins and creoles. 1. Introduction It is a truth widely acknowledged that developments in bilingual individuals par- allel, and ultimately underlie, those taking place in the course of contact-induced language change: ‘the bilingual individual is the ultimate locus of language con- tact’ (Romaine 1996: 573). In bilingual individuals we observe processes such as code-switching, transfer and other forms of grammatical interaction; in languages in contact, we observe processes such as lexical borrowing, calquing and contact- induced grammaticalization, while the outcomes include language shit, pidgini- zation and creolization. Yet the relationship between the individual and language- level processes remains poorly understood, and this is especially so in the domain of grammaticalization.