to the findings of Chapter 1) and demonstrate some interesting patterns of
acquisition, particularly in relation to word order, that differ somewhat from
the expected patterns of (near-) monolingual speakers of these respective
languages. We discuss possible linguistic and extra-linguistic explanations
for our findings in the context of cross-linguistic influence across the bilin-
gual’s two languages.
Sticking within the theme of cross-language influence, Chapter 4 expands
further on the findings of Chapters 1, 2 and 3 by exploring which aspects (if
any) of bilinguals’ morphosyntactic and semantic systems are most suscep-
tible to interaction in development. Using a series of forced-choice experimen-
tal methods, the data presented explore the extent to which the process of
acquisition, and the ultimate relationship between the two languages, is
dependent on patterns of home language exposure and experience and on the
extent of linguistic similarity across the two languages. In relation to the
morphosyntactic system in English, monolingual English-speaking children
were compared to three types of Welsh-English bilinguals: those receiving
Welsh input at home; those receiving Welsh and English input at home; and
those receiving English input at home (but Welsh at school). The same bilin-
gual children were also tested for their morphosyntactic knowledge in Welsh.
For both languages, early differences were found across the various groups of
children, with those receiving the most input in English performing the best
in English, and those receiving the most input in Welsh performing the best
in Welsh, although some accelerated learning was also observed among the
bilinguals. However, these early differences across participants became neu-
tralised across groups by age 13 to 15 in both languages. The authors go on to
discuss overlapping similarities and differences in bilinguals’ semantic
system(s), and cite evidence from recent studies demonstrating widespread
higher level interactions between the labels used in bilinguals’ two languages
in relation to specific concepts. This chapter proposes a fresh new model to
account for the differences in rates of interaction observed in the semantic and
morphosyntactic domains, which involves a ‘common cognition’ to enable
the processing and development of both languages. Under this account, the
relationship between a bilingual’s two languages is seen as grounded within
the wider, cognitive experience, while influenced by the linguistic environ-
ment in which the languages are developed.
The transfer of patterns (Chapters 1, 2, 3 and 4) and conventional meanings
(Chapter 4) from one language into another is but one example of cross-linguistic
influence. Another example, common to language contact situations, is code-
switching, which is the focus of part three – Bilingual Language Use. Code-
switching involves the (optional) alternation of languages within a single
speech stream, which is largely dictated by linguistic and social conventions.
Chapter 5 describes the process of developing bilingual speech corpora in order
to facilitate research on code-switching, exploring the ways in which bilinguals
living in different types of communities handle their two languages in
xx Advances in the Study of Bilingualism