Mwili unahitaji oksijeni.

• Mwili = body
• unahitaji = needs / is needing
• oksijeni = oxygen

So the structure is very direct: body + needs + oxygen.

The u- is the subject marker that agrees with mwili.

In Swahili, verbs usually include a marker showing who or what is doing the action.
Here:

• mwili belongs to the m-/mi- noun class
• singular nouns in this class usually take the subject marker u-

So:

• mwili unahitaji = the body needs

This agreement is a very important part of Swahili grammar.

The dictionary form is kuhitaji, which means to need.

You can break unahitaji into parts like this:

• u- = subject marker for mwili
• -nahitaji- = present tense + verb stem

A beginner-friendly way to think of it is:

• kuhitaji = to need
• unahitaji = it needs / the body needs

It is in the present tense.

The -na- in the verb is the usual Swahili marker for the present tense. So:

• u-na-hitaji
• u- = it/he/she (depending on noun class or subject)
• -na- = present
• -hitaji = need

So unahitaji means needs, is needing, or in context simply needs.

Swahili normally does not use articles like English the and a/an.

So mwili can mean:

• a body
• the body
• body (depending on context)

In this sentence, the natural English translation is The body needs oxygen, but Swahili does not need a separate word for the.

Yes, this sentence uses the very common Subject–Verb–Object order:

• Mwili = subject
• unahitaji = verb
• oksijeni = object

So it matches English quite closely:

• The body
  • needs
    • oxygen

That makes this sentence relatively easy for English speakers to understand.

Oksijeni is a borrowed word, adapted from oxygen.

Swahili has many loanwords, especially for scientific, modern, or technical vocabulary. The spelling is adjusted to fit Swahili sound patterns, so oxygen becomes oksijeni.

This is very common in Swahili and nothing unusual.

A helpful approximation is:

ok-si-JE-ni

A few pronunciation tips:

• Swahili vowels are usually pronounced clearly and consistently.
• Each vowel is normally sounded.
• The stress often falls near the second-to-last syllable, so JE is the strongest part here.

An English speaker should avoid reducing the vowels too much.

Mwili belongs to the m-/mi- noun class:

• singular: mwili = body
• plural: miili = bodies

This matters because nouns in Swahili affect agreement in verbs, adjectives, and other parts of the sentence.

For example:

• mwili unahitaji = the body needs
• miili inahitaji = bodies need

Notice how the verb changes:

• singular u-
• plural i-

So noun classes are not just about singular and plural; they also control agreement.

You would say:

Miili inahitaji oksijeni.

Changes:

• mwili → miili = body → bodies
• unahitaji → inahitaji = needs → need, agreeing with the plural noun class

So:

• Mwili unahitaji oksijeni. = The body needs oxygen.
• Miili inahitaji oksijeni. = Bodies need oxygen.

No, that would be incorrect in standard Swahili.

The subject marker is normally required on the verb, even when the subject noun is already stated.

So you need:

• Mwili unahitaji oksijeni.

not:

• Mwili wahitaji oksijeni

This is one of the big differences from English: Swahili verbs usually carry agreement marking.

A natural negative form is:

Mwili hauhitaji oksijeni. = The body does not need oxygen.

Here:

• hau- is the negative subject form that agrees with mwili
• -hitaji stays as the verb meaning need

So compare:

• Mwili unahitaji oksijeni. = The body needs oxygen.
• Mwili hauhitaji oksijeni. = The body does not need oxygen.

Usually mwili means a physical body. In many contexts it is straightforward and literal.

Depending on context, it can also be used in broader ways, such as referring to a main body or substantial form of something, but for a learner, the safest and most common meaning is simply body.

In this sentence, it clearly means the physical body.