Wasiponunua maziwa leo, tutakunywa chai bila maziwa kesho asubuhi.

Wasiponunua can be divided like this:

• wa- = they
• -si- = negative
• -po- = if / when
• -nunua = buy

So wasiponunua means if they do not buy.

This is a very common Swahili pattern for a negative condition:

• wasipokuja = if they do not come
• usipoenda = if you do not go
• nisipopata = if I do not get

Wa- is the subject marker for they referring to people.

So:

• wa- = they
• tu- = we
• u- = you (singular)
• ni- = I

In this sentence, the people who may or may not buy the milk are they, so the verb begins with wa-.

In Swahili, subject information is usually built into the verb itself, so separate subject pronouns are often unnecessary.

For example:

• wasiponunua already includes they
• tutakunywa already includes we

So Swahili often says:

• tutakunywa = we will drink rather than using a separate pronoun like sisi tutakunywa, unless the speaker wants emphasis.

Tutakunywa breaks down like this:

• tu- = we
• -ta- = future
• -kunywa = drink

So tutakunywa means we will drink.

Compare:

• ninakunywa = I am drinking
• nitakunywa = I will drink
• tunakunywa = we are drinking
• tutakunywa = we will drink

Because the sentence means:

• If they do not buy milk today → negative condition
• we will drink tea without milk tomorrow morning → positive result

So the first part uses a negative conditional form:

• wasiponunua = if they do not buy

The second part is simply a future statement:

• tutakunywa = we will drink

This matches English logic too: If they don’t buy..., we will drink...

Maziwa means milk, but grammatically it looks like a plural noun in Swahili.

It belongs to noun class 6, which often has the prefix ma-. Even though milk is uncountable in English, Swahili uses maziwa as the normal word.

So you should simply learn:

• maziwa = milk

Even though it starts with ma-, you do not translate it as milks in normal usage.

Because the sentence literally says:

• If they do not buy milk today
• we will drink tea without milk tomorrow morning

The second maziwa is needed because bila means without, and it must be followed by the thing that is absent:

• bila sukari = without sugar
• bila maji = without water
• bila maziwa = without milk

So repeating maziwa is completely natural.

Bila means without.

In this sentence:

• chai bila maziwa = tea without milk

It is a very useful word and does not need a verb after it. It simply introduces what is lacking.

Examples:

• kahawa bila sukari = coffee without sugar
• anaenda bila viatu = he/she is going without shoes
• bila shida = without problem / no problem

Because each time expression belongs to a different action:

• leo modifies wasiponunua = if they do not buy milk today
• kesho asubuhi modifies tutakunywa = we will drink tea tomorrow morning

So the sentence contrasts two times:

• the buying happens or fails to happen today
• the consequence happens tomorrow morning

This is very natural Swahili word order.

Kesho asubuhi means tomorrow morning.

It is made of:

• kesho = tomorrow
• asubuhi = morning

Together they specify the time more precisely.

You can also see similar expressions like:

• leo asubuhi = this morning
• kesho jioni = tomorrow evening
• jana usiku = last night

Swahili word order is somewhat flexible, but this version is very natural:

Wasiponunua maziwa leo, tutakunywa chai bila maziwa kesho asubuhi.

Why it feels natural:

• the if-clause comes first
• the result comes second
• time words are placed near the actions they describe

You could move some elements for emphasis, but for a learner this is a good standard pattern:

• [condition], [result]

Yes, Swahili can use kama for if, but in this sentence the conditional meaning is already built into the verb with -po-.

So instead of saying something like:

• kama hawatanunua...

Swahili here uses:

• wasiponunua...

This is a compact and very common way to express if they do not...

For learners, it is useful to recognize that Swahili often puts conditional meaning inside the verb itself, not just in a separate word.

Hawatanunua means they will not buy, which is a plain future negative statement.

But wasiponunua means if they do not buy, which is a conditional form.

So the difference is:

• hawatanunua maziwa leo = they will not buy milk today
• wasiponunua maziwa leo = if they do not buy milk today

Since this sentence is an if... then... sentence, wasiponunua is the right form.

Yes. A useful pattern is:

[negative conditional verb] + [thing] + [time], [future verb] + [result] + [time]

In this sentence:

• Wasiponunua maziwa leo = If they do not buy milk today
• tutakunywa chai bila maziwa kesho asubuhi = we will drink tea without milk tomorrow morning

You can build similar sentences:

• Usiposoma leo, utafeli kesho.
  If you do not study today, you will fail tomorrow.

• Wasipokuja mapema, tutaanza bila wao.
  If they do not come early, we will start without them.

This makes the structure easier to reuse.