The infinitive form in Swahili, defined as Ku plus the verb stem: kusema, to speak, has three functions which we can identify as:
3. Nominal (as a noun)
The following sentence constructions can be distinguished:
Naenda sokoni kununua vitu. I go to the market to buy things.
Utakuja lini kutuamkia? When will you come to greet us?
Siwezi kutengeneza gari. I am unable to repair the car.
Nitakusaidia kutafuta kazi. I will help you to look for work.
Watumaini kuendelea na masomo? Do you hope to continue with
2. The infinitive is used as the second of two verbs in a sentence if the subject of both is the same and there is no reference to the order of the actions. The tense used in the first verb also applies to the infinitive. With negative tenses the connecting word wala is used rather than na.
Wanaingia na kutoka. They go in and out.
Tulikula na kunywa. We ate and drank.
Nitafua na kusafisha nyumba. I shall wash clothes and clean
Hakusoma wala kuandika. He neither read nor wrote.
Hawaoni wala kusikia. They neither see nor hear.
3. The infinitive form preceding a verb concentrates the attention on the action:
For example, a person asked whether it is going to rain. The answer was: Kunyesha itanyesha. As for raining, it is going to rain.
This gives no indication as to the character of the raining; that may be done in another clause:
Kunyesha itanyesha, lakini labda itakuwa manyunyu tu. As for raining, it will rain but maybe it will only drizzle.
Kusoma alisoma. As for reading, he read.
Kusafisha amesafisha. As for cleaning she has cleaned.
Baada ya mizigo kuangaliwa walitafuta hoteli. After taking care of the luggage they looked for a hotel.
Kabla ya mkutano kufanyika walipanga viti.
Before holding the meeting they arranged the chairs.
Afadhali kufanya kazi.
It's better to work (for anyone).
Alikimbia kwa kukimbia kweli. He ran like the wind.
Alilia kwa kulia kama nini. She cried a flood of tears.
Amefurahi kwa kufurahi ajabu. She is bursting with joy.
This is limited to its occurrence in phrases with the A of relationship. The basic form of the infinitive may be used, or any of its derivational forms. When the prepositional form is used, it specifies the use to which the described item will be put. See paragraph 30.A.1&2.
mkate wa kutosha enough bread
maneno ya kupendeza pleasing words
maneno ya kuaminika believable words
mashirikia ya kujitolea voluntary agencies
chumba cha kulia dining room
chumba cha kuogea bathroom
chumba cha kulala bedroom
When used as a noun, the infinitive requires a full set of prefixes for CL.15 nouns. These are discussed in paragraph 10, Class 15 nouns. The use of infinitive as a noun is not uncommon, especially when an abstract noun is lacking in Swahili.
Kuuliza si ujinga.
Asking is not ignorance (a proverb).
Kusikia si kuona.
Hearing is not seeing (a proverb).
Kupotea njia ndiko kujua njia.
Getting lost on the way is the way to (get to) know the way (proverb).
kuzaliwa kwa mtoto
the birth of the child
tangu kuzaliwa hata kufa
from birth to death
In the following type of sentence the infinitive also acts as a noun; i.e., object of the verb:
Nataka kwenda mjini. I want to go to town.
Aliomba kuondoka mapema. He asked to leave early.