Ukiwa na mafua na kukohoa usiku, ni vizuri kunywa maji ya uvuguvugu.

Ukiwa comes from the verb kuwa = to be.

It breaks down like this:

• u- = you (singular)
• -ki- = a marker often meaning if or when
• -wa = the verb stem from kuwa

So ukiwa means if you are or when you are.

In this sentence, it is followed by na mafua, so ukiwa na mafua means if/when you have a cold.

Yes. The -ki- form in Swahili often covers both if and when, depending on context.

So:

• ukiwa na mafua can mean if you have a cold
• or when you have a cold

In advice sentences like this one, English often prefers if:

• If you have a cold and are coughing at night, it is good to drink lukewarm water.

Not exactly.

In ukiwa na mafua, the na is part of kuwa na, which literally means to be with, but is commonly used to mean to have.

So:

• kuwa na mafua = to have a cold

Later, na is just the normal word and:

• mafua na kukohoa = a cold and coughing

So the two na forms look the same, but they do different jobs here:

• kuwa na = to have
• na = and

Mafua usually means a cold, especially the kind with a runny nose or nasal congestion.

English speakers sometimes wonder whether it means cold or flu. In everyday Swahili, it usually refers more to cold symptoms than to medically precise influenza.

A useful way to think of it is:

• mafua = a cold / cold symptoms

Also, mafua is normally used in this form; learners should not expect a common everyday singular form for it.

Here kukohoa is the infinitive form of the verb to cough, and infinitives in Swahili can also work like nouns.

So kukohoa here is like saying:

• coughing

That means mafua na kukohoa is roughly:

• a cold and coughing

If the sentence had ukikohoa, that would mean:

• if/when you cough

So the difference is:

• kukohoa = coughing as a condition or symptom
• ukikohoa = if/when you cough as a separate clause

In Swahili, many time expressions do not need a preposition like at, in, or on.

So:

• usiku = at night
• asubuhi = in the morning
• mchana = during the day
• leo = today

That means:

• kukohoa usiku = to cough at night / coughing at night

This is very normal Swahili structure.

Ni vizuri is a very common expression meaning it is good, it is advisable, or it is better.

Here, vizuri is being used in an impersonal, adverb-like way. It does not directly describe a noun.

By contrast, nzuri is an adjective used to describe a noun:

• maji mazuri = good water
• wazo zuri = a good idea

But:

• ni vizuri kunywa maji ya uvuguvugu = it is good/advisable to drink lukewarm water

So this sentence needs ni vizuri, not ni nzuri.

Kunywa is the infinitive form of to drink.

In Swahili, infinitives can function a bit like nouns, so after expressions like ni vizuri, you can use an infinitive phrase.

That is why:

• ni vizuri kunywa... = it is good to drink...

This pattern is very common:

• Ni vizuri kupumzika = It is good to rest
• Ni muhimu kula vizuri = It is important to eat well

So kunywa maji ya uvuguvugu means to drink lukewarm water.

Literally, maji ya uvuguvugu means something like:

• water of lukewarmness
• or water of gentle warmth

In more natural English, that becomes:

• lukewarm water

The word uvuguvugu refers to the state or quality of being lukewarm.

The connector ya links maji and uvuguvugu. This connector changes depending on the noun class of the first noun, and maji takes ya.

So:

• maji ya uvuguvugu = lukewarm water

Grammatically, maji belongs to noun class 6, which often behaves like a plural class. But in meaning, maji is usually an uncountable mass noun: water.

That is why learners sometimes feel confused: it does not behave exactly like English water.

Because maji is in this noun class, it takes connectors and agreement forms such as ya.

So:

• maji ya uvuguvugu uses ya because of the noun class of maji

Even though maji means water, not waters, its grammar follows Swahili noun-class rules, not English singular/plural logic.

The sentence has two main parts:

• Ukiwa na mafua na kukohoa usiku = the condition: if/when you have a cold and are coughing at night
• ni vizuri kunywa maji ya uvuguvugu = the advice: it is good to drink lukewarm water

So the pattern is:

• condition + advice

A useful way to see it is:

• Ukiwa... = If/When you are...
• ni vizuri... = it is good/advisable...

This is a very common and natural way to give advice in Swahili.