Verb Extensions

Verb extensions are a core building block of Swahili. By adding a small suffix to a verb root, you can completely change its meaning and how it interacts with other words in the sentence.

Here are the most common types of extensions you will encounter:

• Passive: The subject receives the action. See Passive -wa.
• Applicative: The action is done for, to, or at someone or something. When used for animate beneficiaries (people or animals), this extension requires adding an object marker to the verb. However, an object marker is generally not needed when the applicative is used for locations (e.g., kukimbilia - to run towards) or instruments. See Applicative -ia and Applicative -ea.
• Causative: Making someone or something do the action. See Causative -isha and Causative -esha, as well as fused, irregular forms like -za and -ya (e.g., the root -jaa becomes -jaza).
• Stative: Describes a state of being or potential (e.g., "is broken"). See Stative -ika and -eka.
• Reciprocal: Doing an action to each other. See Reciprocal -ana.
• Reversive: Undoing or reversing an action. See Reversive Extension and Intransitive Reversive.

How they work:
Extensions attach directly to the verb root. For native Bantu verbs ending in -a, they are inserted right before this final vowel. For Arabic loanwords ending in -e, -i, or -u, the final vowel is usually dropped before adding the standard extension (e.g., -rudi becomes -rudia, and -jibu becomes -jibia or -jibiwa), though the passive often just adds -wa to some -e and -i verbs (e.g., -samehewa, -rudiwa). Additionally, if a native verb root ends in two consecutive vowels (like -nunua) or is an Arabic loanword ending in -au (like -sahau), an -l- is often inserted between the root and the extension (for example, -nunua becomes -nunulia), or the extensions themselves take an l-initial form (like -lia, -lewa, or -lika). The exact vowel used in the extension depends on the vowels inside the verb root—a concept called vowel harmony. If the root contains a, i, or u, the extension uses i (like -ia or -ika). If the root contains e or o, the extension uses e (like -ea or -eka). Note that short, monosyllabic verbs (like -la, -ja, -nywa, or -pa) have irregular or unpredictable extension forms. They often require an inserted -li- or -le- (for example, the root -la becomes -liwa or -lika) or have unique forms (like -pewa). You can even stack multiple extensions together (for example, combining the applicative and passive: -pika becomes -pikia, which then becomes -pikiwa). While they follow a general Verb Extension Order, the order of middle extensions (like applicative, causative, and reciprocal) can sometimes be swapped depending on the specific meaning you want to convey.