-si-

Negative Subjunctive

Level 3

The negative subjunctive -si- is the standard way to tell someone not to do something in Swahili. It is also used to express negative purpose ("so that... not") and negative obligation ("should not").

How It Works

The negative subjunctive is incredibly common because Standard Swahili does not use a separate negative imperative form. For direct, personal negative commands, you will use this structure (though general public prohibitions often use the negative infinitive, like kutovuta sigara for 'no smoking').

Key Rules:

  • Subject Prefixes: The verb must start with a subject prefix matching who you are talking to or about (e.g., u- for singular 'you', m- for plural 'you all', a- for 'he/she', wa- for 'they').
  • Native Bantu Verbs: Add the subject prefix and -si-, then change the final -a to -e (e.g., chelewa → u-si-chelew-e).
  • Arabic Loanwords: Verbs ending in -i, -e, or -u do not change their final vowel (e.g., sahau → u-si-sahau).
  • Object Prefixes: If using an object prefix, it goes between the -si- and the verb root (e.g., u-si-m-pig-e).
  • Dropping ku-: All verbs drop the infinitive ku- marker in the subjunctive. This is especially important to remember for monosyllabic verbs (like kula → u-si-le), since learners are used to keeping it in other tenses.

Main Uses:
1. Negative Commands: Usiende! (Don't go! - singular) or Msiende! (Don't go! - plural). Note: Usende is a common spoken contraction.
2. Suggestions and Deliberations: Using first-person prefixes for 'Let's not...' or 'Should I not...?' (e.g., Tusiende. - Let's not go; Nisiende? - Should I not go?).
3. Negative Purpose: Often triggered by the conjunction ili (so that), though it can sometimes be dropped in speech. Example: Funga mlango ili paka asitoke. (Close the door so the cat doesn't get out.)
4. Negative Obligation: After verbs of desire or necessity (e.g., Nataka usiseme... / I want you not to say...).

Examples (5)

  1. Usichelewe!

    Don't be late!

    Word by Word: You-not-be.late

    A direct negative command using the second-person singular prefix u-.

  2. Nataka utoe onyo kwa watoto wasipande juu ya meza.

    I want you to give a warning to the children so they don't climb on the table.

    Word by Word: I.want you.give warning to children they.not.climb top of table

    Shows negative purpose ("so they don't climb") using the class 2 prefix wa-.

  3. Tusije tukapoteza muda.

    Lest we end up wasting time. / Let's not waste time.

    Word by Word: We.not.come we.waste time

    A common expression using the negative subjunctive of kuja (to come) to mean "lest".

  4. Tafadhali usisahau kitabu chako.

    Please don't forget your book.

    Word by Word: Please you.not.forget book your

    Notice that the Arabic loanword sahau does not change its final vowel to -e.

  5. Daktari alisema nisile sukari.

    The doctor said I shouldn't eat sugar.

    Word by Word: Doctor he.said I.not.eat sugar

    Shows negative obligation. The monosyllabic verb kula drops its ku- to become -le.

Common Mistakes

  • Confusing the negative subjunctive with the negative present tense.

    Different MeaningSisomi kitabu hiki.
    Nisisome kitabu hiki.

    Sisomi means "I am not reading" (negative present). Nisisome means "I shouldn't read" (negative subjunctive). The negative subjunctive uses affirmative subject prefixes and the -si- infix.

  • Retaining the ku- on monosyllabic verbs.

    Usikule chakula hiki.
    Usile chakula hiki.

    In Standard Swahili, monosyllabic verbs must drop the ku- in the subjunctive. (Note: usikule is common in Kenyan slang, but incorrect in standard grammar).

  • Changing the final vowel of Arabic loanwords.

    Usijaribe kufanya hivyo.
    Usijaribu kufanya hivyo.

    Verbs of Arabic origin ending in -i, -e, or -u (like jaribu) never change their final vowel in the subjunctive.

How It Connects

Tap a pattern to see what it builds on and what it leads to.

-si-Level 3Negative Subjunctive

Learn This First

To understand the negative subjunctive, you must first be familiar with the basic subjunctive mood (ending in -e) and how subject markers are attached to verbs. The negative subjunctive uses the marker -si- between the subject marker and the verb root to express purpose or commands in the negative.

Words in This Pattern

-si-