kuwa

The verb kuwa is one of the most frequent words in Swahili. Here is how it works:

• Past, Future, and Perfect: To say someone 'was', 'will be', or 'has been' something, attach the subject and tense markers directly to kuwa. For example, a-li-kuwa (he/she was), ni-ta-kuwa (I will be), or ni-me-kuwa (I have been / I have become).
• The Present Tense Exception: For identity or state, Swahili uses the invariable word ni (and si for the negative). For location, it uses locative suffixes like -ko, -po, or -mo attached to a subject prefix (e.g., niko for 'I am located'). Note the highly irregular 3rd-person singular prefix yu- for Class 1 people and animals (e.g., yuko for 'he/she is located', not ako). Objects use their respective noun class prefixes (e.g., kiti kiko for 'the chair is located' or gari liko for 'the car is located'). Do not conjugate kuwa with the present tense marker to say 'I am'; a word like ninakuwa actually means 'I am becoming'.
• Habitual 'To Be': While ni is used for a current state or identity, to say something 'usually is' or 'usually happens', use the habitual form huwa.
• Keeping the 'ku-': Swahili words require stress on the second-to-last syllable. In standard tenses (past, future, perfect), the ku- prefix is retained to provide that extra syllable. However, it is dropped in forms that don't need it, like the subjunctive (niwe) or present negative (siwi, which means 'I do not become' or 'I am not usually', distinct from the present negative copula si meaning 'I am not').
• Negating Past and Future: When negating kuwa, the future tense keeps the ku- (e.g., sitakuwa = I will not be). However, in the past tense, the past negative marker -ku- replaces the infinitive ku- (e.g., sikuwa = I was not; sikuwa na = I did not have).
• To Have: Combining kuwa with na creates the verb kuwa na (to have). In the present tense, the word kuwa is dropped entirely, and the subject prefix attaches directly to -na (e.g., nina = I have; ana = he/she has). For the negative, attach the negative subject prefix directly to -na (e.g., sina = I do not have; hana = he/she does not have). In the past and future tenses, kuwa is retained and na remains a separate word (e.g., nilikuwa na = I had; nitakuwa na = I will have).
• There Is / There Are: To say 'there is' or 'there are', Swahili uses locative prefixes with -na. The most common is kuna (there is/are generally), but you will also see pana (there is/are at a specific place) and mna (there is/are inside).
• Helping Verb: Kuwa is also used as an auxiliary (helping) verb to create compound tenses, like 'we were reading'.

Recognizing a Spoken Variant:
The careful standard past-negative form is sikuwa (I was not), with no extra infinitive ku-. You may hear sikukuwa in regional informal usage, notably in Kenya. Recognize that variant while using sikuwa as the model for formal standard writing.