This paper investigates the effects of Dutch on the tense-aspect system of heritage Ambon Malay, a variety spoken by Dutch-Ambon Malay bilinguals in the Netherlands. The study asks whether the cross-linguistic contrasts between the two languages – Dutch obligatorily marks past/non-past and finiteness, whereas Ambon Malay lacks a grammaticalized expression of these distinctions – has an effect on the aspectual system of heritage Ambon Malay.

The database for the study consists of video descriptions provided by 32 bilingual speakers (the experimental groups) and by three control groups: 27 homeland speakers of Ambon Malay, 5 first generation speakers of Ambon Malay in the Netherlands (late bilinguals), and 10 monolingual speakers of Dutch.

The frequency and distribution of aspect markers is analysed statistically in the four groups.

The analysis of the data reveals that, under the influence of Dutch, the Ambon Malay progressive marker ada has undergone a shift in temporal status and frequency and it is now interpreted as a marker of present tense, as well as of progressive aspect. The other two aspect markers, the iamitive/perfective su and verbal reduplication (iterative) are used significantly less by heritage speakers.

This study shows that when a grammatical category is present and productive in the dominant language of a bilingual heritage speaker, but not in the heritage language, there is a great likelihood that it will undergo contact-induced grammaticalization, even in a relatively short time contact situation. The study also shows that input-related factors, such as transparency and phonological salience, contribute to the (in)stability of aspectual forms in the heritage language.

This finding has implication for the incomplete acquisition perspective on heritage languages, which sees these languages as grammatically simplified systems (see, e.g., Montrul, 2009; Polinsky, 2008), because it shows that heritage languages can also gain grammatical distinctions previously absent in the (homeland) language.