Ukivuta hewa safi nje, mapafu yako yatakuwa na nguvu zaidi.

Ukivuta is a whole chunk that already expresses the idea of “if/when you breathe (in)”.

Breakdown:

• u- = subject prefix for “you” (singular)
• -ki- = conditional/temporal marker meaning “if/when/whenever”
• vut- = verb root “to pull / draw / inhale / smoke”
• -a = final vowel for the basic verb form

So ukivuta literally is “you-if/when-pull(inhale)”.
In natural English: “if you breathe in” or “when you breathe in”.

That’s why there is no separate word like “if” before it—the -ki- is doing that job.

Yes, vuta has several related meanings:

• to pull / draw (physically)
• to inhale / breathe in
• to smoke (a cigarette, etc.) — literally “to draw/inhale smoke”

In this sentence, vuta hewa means “to draw in air,” “to inhale air,” which is completely natural in Swahili.

Context removes the “smoke” meaning:

• kivuta sigara = you smoke a cigarette
• kivuta hewa safi = you inhale fresh/clean air

Because of hewa safi (“clean/fresh air”), it clearly means “breathe in”, not “smoke.”

In clauses with -ki- (like ukivuta), Swahili often uses a “general/present” feeling that covers:

• Whenever you do X
• If you do X
• When you do X (in the future or habitually)

So Ukivuta hewa safi nje can be understood as:

• “When you breathe fresh air outside,”
• “If you breathe fresh air outside,”
• “Whenever you breathe fresh air outside.”

The future is then clearly marked in the main clause:

• mapafu yako yatakuwa… = “your lungs will be…”

So time is really fixed by the main clause (future yatakuwa), while ukivuta stays the more general “if/when you breathe.”

Swahili has two common ways to express “if/when”:

1. Using kama

   • a normal verb:
   • Kama unavuta hewa safi nje, …
     “If you breathe fresh air outside, …”

2. Using the -ki- form inside the verb:

   • Ukivuta hewa safi nje, …
     “If/when you breathe fresh air outside, …”

Both are correct. Differences:

• The -ki- form (ukivuta) is very natural and common, especially in speech, for “if/when/whenever”.
• kama can emphasize the conditional “if,” sometimes with a stronger sense of “on condition that.”

Here, Ukivuta… on its own is completely normal and doesn’t need kama.

mapafu means “lungs” and belongs to noun class 6 (ma‑ class).

Class 6 subject agreement is ya- in the present/future. That’s why we get:

• mapafu (lungs) → class 6 noun
• ya- (subject prefix for class 6 in this tense)
• -ta- (future marker “will”)
• kuwa (to be)

So:

• yatakuwa = ya‑ta‑kuwa → “(they) will be”

Because mapafu is plural, yatakuwa also agrees with it as “they will be.”

Possessive adjectives in Swahili must agree with the noun class of the thing possessed.

• mapafu is class 6.
• The class 6 possessive prefix is ya-.
• For “your (singular)”, the possessive ending is -ko.

Combine them:

• ya-
  • -ko → yako = “your” (agreeing with a class 6 noun)

So:

• mapafu yako = “your lungs” (with correct class agreement)

wako is used with class 1/2 (people, like mtu, rafiki), not with mapafu.

Literal breakdown:

• yatakuwa = “they will be”
• na = “with / having”
• nguvu = “strength / power / energy”
• zaidi = “more”

So literally:
“they will be with more strength” or “they will have more strength.”

In natural English, we normally say “they will be stronger.”
Swahili often expresses “to be X-adjective” using kuw(a) na + noun, e.g.:

• Atakuwa na furaha nyingi.
  Literally: “He will be with much happiness.”
  Naturally: “He will be very happy.”

Same pattern here:
yatakuwa na nguvu zaidi → “they will be stronger.”

Yes, you can, and it is grammatical. The difference is subtle:

• na nguvu zaidi = “with more strength”
  → very common, straightforward “will have more strength / be stronger.”

• yenye nguvu zaidi = “(ones) that have more strength / that are strong”
  → uses -enye, an adjective meaning “having / possessing”.

So:

• mapafu yako yatakuwa na nguvu zaidi
  = “your lungs will have more strength / will be stronger.”

• mapafu yako yatakuwa yenye nguvu zaidi
  = “your lungs will be stronger (ones that have more strength).”

Both are okay; na nguvu zaidi is more everyday and slightly simpler.

hewa = “air”
safi literally means “clean / pure”, and by extension “fresh” in some contexts.

So hewa safi can be understood as:

• clean air
• fresh air
• pure air

In this sentence, English “fresh air” is the most natural translation, but “clean air” is just as accurate for the Swahili phrase.

nje means “outside / outdoors.” It’s an adverb of place.

In this sentence:

• hewa safi nje = “fresh/clean air outside”

Typical positions for nje:

• After the verb: Toka nje. = “Go outside.”
• After the noun it describes: hewa safi nje = “fresh air outside.”

You could also reorder a bit, e.g.:

• Ukivuta hewa safi ukiwa nje, …
  “If you breathe fresh air when you are outside, …”

But Ukivuta hewa safi nje, … is natural, compact, and clear.

The comma after nje in

Ukivuta hewa safi nje, mapafu yako yatakuwa na nguvu zaidi.

separates:

• the conditional clause: Ukivuta hewa safi nje
• from the main clause: mapafu yako yatakuwa na nguvu zaidi

This is the same as in English: > “When you breathe fresh air outside, your lungs will be stronger.”

In actual Swahili writing:

• The comma is standard and recommended, especially in formal text.
• In casual writing, people might sometimes leave it out, but the sentence is clearer and more correct with the comma.