Must in Singapore English

In Singapore English, the modal verb must is predominantly deontic, in contrast with the usage profile of must in most native varieties of English. I account for this variation in terms of three linguistic factors prevalent in the contact ecology of Singapore English. First, the deontic and epistemic modalities are expressed by different modal expressions in Chinese, the main substratum language. Second, the perfect form have V-en has experienced a sharp decline in Singapore English, which contributes to the decline of the epistemic must. Third, the grammaticalization path that must has undergone in English is not followed by the equivalent expressions in Chinese. These three factors exert convergent pressure on must towards the deontic modality. The paper demonstrates the importance of computerized corpora in the study of contact-induced linguistic change.