Learn Hardcore Swahili: Kama bei ingekuwa nafuu, mama angenunua kompyuta kwa watoto. - If the price were cheaper, mother would buy a computer for the children.

Class 9 subject prefix is i- → ingekuwa = “it (the price) would be”.
angekuwa would have a-, the class 1 human subject prefix → “he/she would be”.
kingekuwa would use ki-, the class 7 subject prefix (wrong for bei).

So ingekuwa is correct agreement with bei.

Do both verbs in this kind of sentence have to use -nge-?

For a clearly unreal / hypothetical condition, it is normal and preferred to use -nge- in both clauses:

Kama bei ingekuwa nafuu, mama angenunua kompyuta…

You sometimes hear only one -nge- in casual speech, but the standard pattern is:

kama + (subject + -nge- + verb), (subject + -nge- + verb)

This mirrors English “If X were…, Y would…”.

Can I change the word order and put the mama part first?

Yes. Both orders are fine:

Kama bei ingekuwa nafuu, mama angenunua kompyuta kwa watoto.
Mama angenunua kompyuta kwa watoto kama bei ingekuwa nafuu.

The meaning is the same. The comma is just punctuation; in speech it’s a pause.

What exactly does kama mean here? Are there alternatives for “if”?

Here kama means “if” (not “like/as”).

Common alternatives meaning “if / in case / provided that” include:

ikiwa
iwapo
endapo

For example:

Iwapo bei ingekuwa nafuu, mama angenunua kompyuta kwa watoto.

kama is the most frequent and neutral, especially in everyday speech. iwapo/ikiwa/endapo sound a bit more formal/literary.

What nuance does nafuu have? Could I say bei ingekuwa rahisi instead?

You can say bei ingekuwa rahisi, but nafuu and rahisi are not identical in feel:

nafuu: cheaper / more affordable / at a good or reduced price; often relative (“cheaper than before”, “relatively cheap”, “good deal”).
rahisi: cheap, low price; can be absolute and can sometimes imply too cheap / low quality in some contexts.

In many real-life contexts, sellers will prefer nafuu to sound positive and reassuring.

So:

bei ingekuwa nafuu ≈ “the price would be affordable / reasonable.”
bei ingekuwa rahisi ≈ “the price would be cheap (low).”

What does kwa do in kompyuta kwa watoto? Why not wa watoto?

kwa watoto here means “for the children” – it marks the beneficiary / recipient:

kompyuta kwa watoto = “a computer for the children.”

If you used wa watoto, that would be the possessive “of the children”:

kompyuta ya watoto / kompyuta wa watoto (with the right agreement) = “the children’s computer.”

So:

kwa watoto → emphasizes for whose benefit the computer is bought.
wa watoto / ya watoto → emphasizes whose computer it is (ownership).

Are the children direct objects of the verb here? Why isn’t there an object marker on the verb for them?

No. The direct object of angenunua is kompyuta (the thing being bought).

The phrase kwa watoto marks a beneficiary / indirect object (“for the children”), introduced by kwa. In Swahili:

Direct objects are normally the ones that can be replaced by a direct object marker on the verb.
Indirect objects introduced by prepositions like kwa, kwa ajili ya, kwa ajili ya watoto, etc., typically are not marked on the verb.

So mama angenunua kompyuta kwa watoto is like English “Mum would buy a computer for the children,” not “Mum would buy the children.”

Does mama here mean “Mum/my mother”, or just “a mother/woman”?

By itself, mama literally means “mother”, but in actual use it can be:

a specific Mum (often understood as “my/our Mum” from context), e.g. children talking:
- Mama atanunua kompyuta = “Mum will buy a computer.”
a generic mother / woman, depending on context.

To make “my Mum” explicit, you can say:

mama yangu = my mother
mama yetu = our mother

In your sentence, without extra context, mama is best read as “(the) mother / Mum” in a generic or context‑dependent way.

Is kompyuta the normal Swahili word for “computer”?

Yes, kompyuta is very widely used and understood; it’s a borrowing from English computer.

There is also a more “pure Swahili” coinage:

tarakilishi = computer (you’ll see this more in some Kenyan official/educational contexts).

But in everyday speech across much of East Africa, kompyuta is by far the more common and natural choice.

Does this sentence refer to the present/future, or can it also describe an unreal past situation?

The -nge- conditional in Swahili is time‑flexible; it covers what English would express as:

“If the price were cheap, Mum would buy…” (unreal present/future), and
“If the price had been cheap, Mum would have bought…” (unreal past),

depending on context and time adverbs:

Kama bei ingekuwa nafuu leo, mama angenunua kompyuta…
→ unreal today/future.
Kama bei ingekuwa nafuu jana, mama angenunua kompyuta…
→ unreal yesterday; often understood like “would have bought”.

Speakers can add extra structure (e.g. perfect forms) to make the “would have bought” sense even clearer, but -nge- itself does not fix the time.

How would you say this sentence in the negative, e.g. “If the price were not cheap, Mum would not buy a computer for the children”?

You negate the -nge- forms by inserting -si- after the subject prefix, which in practice fuses into forms like isinge-, asinge-.

One natural negative version is:

Kama bei isingekuwa nafuu, mama asingenunua kompyuta kwa watoto.
If the price were not cheap, Mum would not buy a computer for the children.

Breakdown:

isingekuwa = i-si-nge-kuwa → “it would not be”
asingenunua = a-si-nge-nunua → “she would not buy”