Marking of verb tense in the English of preschool English-Mandarin bilingual children: evidence from language development profiles within subgroups on the Singapore English Action Picture Test.

Background: The phonological and morphosyntactic structures of English and Mandarin contrast maximally and an increasing number of bilinguals speak these two languages. Speech and language therapists need to understand bilingual development for children speaking these languages in order reliably to assess and provide intervention for this population.

Aims: To examine the marking of verb tense in the English of two groups of bilingual pre-schoolers learning these languages in a multilingual setting where the main educational language is English. The main research question addressed was: are there differences in the rate and pattern of acquisition of verb-tense marking for English-language 1 children compared with Mandarin-language 1 children?

Methods & Procedures: Spoken language samples in English from 481 English-Mandarin bilingual children were elicited using a 10-item action picture test and analysed for each child's use of verb tense markers: present progressive '-ing', regular past tense '-ed', third-person singular '-s', and irregular past tense and irregular past-participle forms. For 4-6 year olds the use of inflectional markers by the different language dominance groups was compared statistically using non-parametric tests.

Outcomes & Results: This study provides further evidence that bilingual language development is not the same as monolingual language development. The results show that there are very different rates and patterns of verb-tense marking in English for English-language 1 and Mandarin-language 1 children. Furthermore, they show that bilingual language development in English in Singapore is not the same as monolingual language development in English, and that there are differences in development depending on language dominance.

Conclusions: Valid and reliable assessment of bilingual children's language skills needs to consider the characteristics of all languages spoken, obtaining accurate information on language use over time and accurately establishing language dominance is essential in order to make a differential diagnosis between language difference and impairment.