Negative Monosyllabic Verbs

Swahili has a small group of monosyllabic (one-syllable) verbs, including -la (eat), -ja (come), -nywa (drink), -fa (die), -wa (be), and -pa (give).

Instead of memorizing arbitrary rules for when to keep the infinitive ku-, remember the Penultimate Stress Rule: Swahili words always place stress on the second-to-last syllable. The ku- acts as a "dummy" syllable to carry this stress when the verb is too short. If another part of the word (like a tense marker or object infix) can take the stress, the ku- is dropped.

Here is how this works in negative tenses:

• Present Negative: Drops ku-. The final -a changes to -i. (e.g., kula → sili [I do not eat], huli [you do not eat], hali [he/she does not eat]). Note: The verb kuwa (to be) is irregular; its present negative is simply si for all persons. For kuwa na (to have), it uses forms like sina, huna, hana.
• Past Negative: Drops ku-. The tense marker itself is -ku-, which takes the stress. (e.g., kula → hakula [he/she did not eat]). Note: The ku you see here is the tense marker, not the infinitive!
• Perfect Negative (Not yet): Prescriptively drops ku- for monosyllabic verbs. The tense marker is -ja-. (e.g., kula → hajala [he/she has not eaten], kunywa → sijanywa [I have not drunk], kuja → hajaja [he/she has not come]). However, while dropping ku- is the prescriptive standard, retaining it (e.g., hajakula, hajakuja) is widely accepted and common, especially in Kenyan Swahili.
• Future Negative: Retains ku- because the tense marker -ta- cannot take stress. The dummy ku- is phonologically required to carry the penultimate stress (e.g., ha-ta-KU-la [he/she will not eat]).
• Negative Commands (Subjunctive): Drops ku-. The final -a changes to -e. (e.g., kula → usile [do not eat], msile [you all do not eat]).
• Negative Infinitive: Retains ku-. The negative prefix kuto- is added before the infinitive. (e.g., kula → kutokula [to not eat]).
• The Object Infix Rule: If you add an object infix (like -ki- for "it") in conjugated tenses, this infix takes the stress, so the ku- is dropped. For example, sitakila (I will not eat it), not sitakikula. Because the verb -pa (give) always requires an object infix, it drops ku- in conjugated forms (e.g., hajanipa [he/she has not given me]). A note on this: the only exception where you see -ku- in these conjugated tenses is when the object infix itself is -ku- (meaning 'you'), e.g., sikupi (I do not give you). However, the infinitive form retains ku- alongside the object infix (e.g., kukila [to eat it], kumpa [to give him/her]).