Editing Chewa language (section)

===Negative tenses===
Negative tenses, if they are main verbs, are made with the prefix {{lang|ny|sí-}}. They differ in intonation from the positive tenses.<ref>Mtenje (1986), p. 244ff.</ref> The negative of the {{lang|ny|-ná-}} tense has the ending {{lang|ny|-e}} instead of {{lang|ny|-a}}:
*{{lang|ny|sí-ndí-gula}} 'I don't buy'
*{{lang|ny|sí-ndi-na-gúle}} 'I didn't buy'

Tenses which mean 'will not' or 'have not yet' have a single tone on the penultimate syllable:
*{{lang|ny|si-ndi-dza-gúla}} 'I won't buy'
*{{lang|ny|si-ndi-na-gúle}} 'I haven't bought (it) yet'

Infinitives, participial verbs, and the subjunctive make their negative with {{lang|ny|-sa-}}, which is added after the subject-prefix instead of before it. They similarly have a single tone on the penultimate syllable:
*{{lang|ny|ndi-sa-gúle}} 'I should not buy'<ref>Stevick et al. (1965), p.222.</ref>
*{{lang|ny|ku-sa-gúla}} 'not to buy'