Tunahitaji kuchuja maji ya bomba kabla ya kunywa.

We need to filter tap water before drinking.

Breakdown of Tunahitaji kuchuja maji ya bomba kabla ya kunywa.

• sisi: we
• kunywa: to drink
• kabla ya: before
• kuhitaji: to need
• kuchuja: to filter
• maji ya bomba: the tap water

Questions & Answers about Tunahitaji kuchuja maji ya bomba kabla ya kunywa.

What does tunahitaji break down into, and what exactly does it express?

Tunahitaji is made of three parts:

• tu- = subject prefix for “we”
• -na- = present tense marker (present / ongoing / general)
• -hitaji = verb root “need”

So tunahitaji literally means “we (are) need(ing)”, and in normal English it covers:

• we need (general statement)
• we are needing / we are in need of (right now)
• sometimes we will need (near future, from context)

In this sentence it’s best translated simply as “we need” in the present.

Why is it kuchuja and not something like tunachuja?

Kuchuja is the infinitive form, “to filter / to strain”.

In Swahili, after verbs like kuhitaji (to need), kupenda (to like), kujaribu (to try), you normally use the infinitive:

• Tunahitaji kuchuja… = We need to filter…
• Ninapenda kunywa chai. = I like to drink tea.

If you said tunachuja, that would be a separate sentence meaning “we are filtering”:

• Tunahitaji. Tunachuja maji ya bomba.
  = We need. We are filtering tap water.

But in the original sentence, the idea is “need to do X”, so the infinitive kuchuja is correct.

What does kuchuja literally mean, and is it specific to water?

Kuchuja = to filter / to strain / to sieve.

It’s not only for water. You can use it for:

• kuchuja maji – to filter water
• kuchuja mafuta – to filter oil
• kuchuja juisi – to strain juice
• kuchuja unga – to sieve flour

So in this sentence kuchuja maji ya bomba means “to filter the tap water”.

Why is it maji ya bomba? How does this structure work?

Maji ya bomba is literally “water of the tap/pipe”, i.e. tap water.

This uses a very common “X of Y” structure in Swahili:

• maji ya bomba – water of the tap → tap water
• juisi ya machungwa – juice of oranges → orange juice
• kitabu cha Kiswahili – book of Swahili → Swahili book

Pattern:
[thing] + [agreeing possessive particle] + [source/owner]

Here:

• maji = water (noun class 6)
• its agreeing “of” word is ya
• bomba = tap / pipe

So maji ya bomba = water (that comes) from the tap.

Why is it maji ya bomba and not maji la bomba or maji wa bomba?

This is about noun class agreement.

• maji is in noun class 6 (it looks plural but often means a mass: water).
• In class 6, the possessive/genitive “of” word is ya.

Some examples:

• maji ya bomba – water of the tap
• maji ya mvua – rainwater (water of rain)
• maji ya chumvi – salty water (water of salt)

Other classes use different forms, e.g.:

• mtoto wa mama – child of the mother (class 1 → wa)
• kitabu cha mwalimu – teacher’s book (class 7 → cha)

So ya is correct because it must match maji (class 6).

What does bomba mean exactly? Is it just “tap”?

Bomba most commonly means:

• tap / faucet (where water comes out)
• pipe / tube (for liquids or gas)

In context:

• maji ya bomba → tap water
• bomba la maji → water pipe
• bomba la gesi → gas pipe

So in this sentence bomba is understood as tap, and maji ya bomba = tap water.

Why is it kabla ya kunywa and not just kabla kunywa?

In Swahili, when kabla (“before”) is followed by a verb in the infinitive, it normally takes ya:

• kabla ya kunywa – before drinking
• kabla ya kula – before eating
• kabla ya kuondoka – before leaving

Think of kabla ya as a fixed combination when you put a verb after it.

When kabla ya is followed by a noun, it works the same:

• kabla ya chakula – before the meal
• kabla ya safari – before the journey

So kabla ya kunywa is the standard, natural form. Kabla kunywa sounds incomplete or incorrect.

In kabla ya kunywa, what exactly are we “drinking”? Why is the object missing?

The object is understood from context: the tap water we just mentioned.

Full, very explicit Swahili could be:

• Tunahitaji kuchuja maji ya bomba kabla ya kunywa maji hayo.
  We need to filter the tap water before drinking that water.

But because maji ya bomba has just been mentioned, it’s natural and normal in Swahili to omit it and just say:

• kabla ya kunywa – before drinking (it)

English also sometimes omits the object when it’s obvious:

• “Filter the tap water before drinking.” (→ before drinking it)

So the missing object is simply “that water”.

Could I say Tunahitaji kuyachuja kabla ya kunywa instead? How does that change the sentence?

Yes, you can, if the context already makes it clear that “it” refers to water you’ve mentioned earlier.

Explanation:

• kuyachuja = ku- (infinitive) + -ya- (object prefix “it”, agreeing with maji, class 6) + -chuja (filter)

So:

• Tunahitaji kuyachuja kabla ya kunywa.
  = We need to filter it before drinking.

This sounds like you already know you’re talking about water, so you don’t have to repeat maji ya bomba.

If you include both, you’d usually avoid repeating the object prefix:

• Common: Tunahitaji kuchuja maji ya bomba kabla ya kunywa.
• Also possible but a bit heavy: Tunahitaji kuyachuja maji ya bomba kabla ya kunywa.

The original sentence is perfectly natural as it is.

Can I move kabla ya kunywa to the front of the sentence?

Yes. Both of these are correct and natural:

• Tunahitaji kuchuja maji ya bomba kabla ya kunywa.
• Kabla ya kunywa, tunahitaji kuchuja maji ya bomba.

Moving kabla ya kunywa just changes the emphasis slightly:

• Fronted: you first highlight the condition/time (“Before drinking…”), then what must be done.
• Original order: you first state the need (“We need to filter tap water…”), then add when (“before drinking”).

Grammatically, both are fine.

Are there other common ways to say “tap water” in Swahili?

Yes, depending on region and context you may hear:

• maji ya bomba – very common: tap water
• maji ya mfereji – water from a (water supply) channel/pipe; sometimes used like “tap water”
• maji ya mtandao wa maji (more formal/technical) – water from the water network
• maji ya kisima – well water (not tap water, but a useful contrast term)

For everyday conversation, maji ya bomba is widely understood in East Africa as tap water.

How would I say “We don’t need to filter tap water before drinking”?

You just make tunahitaji negative:

• Tunahitaji → Hatuhitaji (we don’t need)

So:

• Hatuhitaji kuchuja maji ya bomba kabla ya kunywa.
  = We don’t need to filter tap water before drinking.

Breakdown of hatuhitaji:

• ha- = negative marker
• -tu- = “we”
• (no -na- here; with ha- the -na- drops)
• -hitaji = need

So hatuhitaji = we do not need.