105 Yang, Hua: The phonological development of a trilingual child ‘International฀Journal฀of฀Bilingualism’฀• ฀Volume฀14฀• ฀Number฀1฀•฀2010,฀105–126|| The phonological development of a trilingual child: Facts and factors Hsueh-Yin Yang, Zhu Hua Meiho Institute of Technology, Ping Tung, Taiwan Birkbeck College, University of London, UK Abstract This article investigates the early phonological development of a trilingual child who is acquiring Spanish, Mandarin and Taiwanese simultaneously. By examining the natural speech data recorded between the age of 1;3 and 2;0, the article reports the age of emergence and stabilization of the vowels and consonants, speech accuracy and phonological error patterns in each language. The data show that by the age of two the child is able to produce most of the vowels in the three languages. However, there are cross-linguistic differences in the rate of acquisition of consonants and speech accuracy: the child’s Spanish consonant inventory develops faster than the other two languages, while the child has statistically significantly higher speech accuracy in Taiwanese than in Spanish, which is in turn higher than that in Mandarin. There is also evidence of interaction or interference between the languages, e.g. the existence of unusual error patterns. These facts are interpreted in the context of phonological saliency of the three phonological systems and language input. 1 Introduction Studies of phonological development of bilingual children present a highly complex and dynamic picture (Zhu & Dodd, 2006). In particular, there are strong indications of interaction and interference between the different phonological systems (Burling, 1959/1978; Fantini, 1985; Itoh & Hatch, 1978; Johnson & Lancaster, 1998; Leopold, 1939–1949; Schnitzer & Krasinski, 1994; Vogel, 1975 and more recently, So & Leung, 2006; Stow & Pert, 2006; cf. Deuchar & Quay, 2000). The interaction or interference can take the form of applying language-specific features to the wrong language, using shared phonemes in the wrong phonotactic position, error patterns that are atypical of mono- lingual children of the same developmental ages and so on. Paradis and Genesee (1996), in their studies of syntactic acquisition of French–English bilingual children, identified three types of interdependence between the developing languages: transfer, acceleration and delay. While transfer involves one feature of one language occurring in the other Key words input Mandarin phonological saliency Spanish Taiwanese trilingual phonological acquisition The International Journal of Bilingualism Copyright © 2010 the Author/s 2010, ISSN; Vol 14 (1): 105–126; ID no 356650; DOI; 10.1177/1367006909356650 http://Ijb.sagepub.com Address for correspondence Dr Zhu Hua, Department of Applied Linguistics and Communications, Birkbeck College, University of London, 43 Gordon Square, Bloomsbury, London, WC1H 0PD, UK. [email: Zhu.hua@bbk.ac.uk]