Tulimwona kiboko mkubwa akitoka kwenye maji jioni.

Tulimwona can be analyzed as:

• tu- = we
• -li- = past tense
• -mw- = object marker meaning him/her (here, it refers to the hippo)
• -ona = see

So Tulimwona literally means we saw him/her/it.

Because -ona begins with a vowel, the object marker appears as mw- here rather than a simpler m- shape.

This is very normal in Swahili. The object marker in the verb often agrees with the object even when the noun itself is also present.

So in:

• Tulimwona kiboko mkubwa

you get both:

• the object marker -mw- in the verb
• the full noun phrase kiboko mkubwa after it

This is not strange or redundant in Swahili. It is a common pattern, especially with specific, definite, or animate objects.

Even though kiboko belongs to the ki-/vi- noun class grammatically, animals are very often treated like animate beings in object marking when you are talking about seeing a particular animal.

So -mw- here works like him/her for an animate being. That is why Tulimwona kiboko mkubwa sounds natural as We saw the big hippo...

This is one of those places where semantic animacy can matter, not just noun class.

Word for word:

• kiboko = hippo / hippopotamus
• mkubwa = big, large

So kiboko mkubwa = big hippo.

In Swahili, adjectives usually come after the noun, unlike in English. So instead of big hippo, Swahili says hippo big.

Also notice that the adjective agrees with the noun class:

• kiboko is in the ki-/vi- class
• so -kubwa becomes mkubwa here

Swahili adjectives usually take a class agreement prefix.

The adjective stem is:

• -kubwa = big

With a noun from the ki-/vi- class in the singular, the agreement is:

• m-

So:

• ki-boko m-kubwa

That gives kiboko mkubwa.

This agreement system is very important in Swahili grammar.

Akitoka comes from the verb -toka, meaning to leave, to come out, to go out, to emerge.

It can be broken down as:

• a- = he/she
• -ki- = a marker often used for an action happening at the same time, or in a kind of while ...-ing sense
• -toka = come out / leave

So akitoka here means something like:

• as it was coming out
• while coming out
• coming out

In natural English for this sentence, it would usually be translated as coming out or as it came out.

Because it refers back to kiboko mkubwa, which is a single hippo.

So:

• a- = he/she/it singular

If it were plural, you would expect a plural subject marker instead.

It is doing a bit of both, but the most helpful way to understand it is that it describes what the hippo was doing at the time we saw it.

So:

• Tulimwona kiboko mkubwa akitoka kwenye maji
• We saw a big hippo coming out of the water

The akitoka part functions a lot like an English participial phrase such as coming out of the water.

Kwenye maji means in the water, at the water, or in this context, with -toka, effectively out of the water / from the water.

Breakdown:

• kwenye = a locative word meaning something like in/on/at
• maji = water

Because the verb is -toka (to come out / come from), the whole phrase is understood as:

• coming out of the water

Both locative strategies exist in Swahili, but kwenye + noun is extremely common in modern Swahili.

So:

• kwenye maji = in/on/at the water
• majini can also mean in the water / in water

In this sentence, kwenye maji is a very natural everyday choice.

Maji is the normal Swahili word for water, and it behaves as a plural-form noun historically and grammatically in many contexts.

This is something learners just have to get used to: the form does not match English expectations exactly.

So even though English treats water as an uncountable noun, Swahili simply uses maji as the standard word.

Jioni means in the evening / evening time.

It is placed at the end because time expressions often come later in the sentence in Swahili, especially after the main event has been stated.

So the sentence flow is:

• We saw
• a big hippo
• coming out of the water
• in the evening

That word order is very natural.

Yes, Swahili often allows some flexibility with adverbials like time expressions.

For example, jioni could appear earlier for emphasis. But the version given:

• Tulimwona kiboko mkubwa akitoka kwenye maji jioni

is very natural and neutral.

Putting jioni at the end is a common way to present the information.

No. Kiboko can also mean whip in other contexts.

That can surprise learners.

But in this sentence, because of:

• kiboko mkubwa
• akitoka kwenye maji

the meaning is clearly hippo, not whip.

Context usually makes the meaning obvious.

Because Swahili often prefers a shorter, more direct structure when the meaning is already clear.

So instead of something heavier like:

• We saw a big hippo that was coming out of the water

Swahili can simply say:

• Tulimwona kiboko mkubwa akitoka kwenye maji

This is elegant and natural. The akitoka phrase already gives the needed information about what the hippo was doing.

A very natural translation is:

• We saw a big hippo coming out of the water in the evening.

Depending on context, you could also say:

• We saw a large hippo coming out of the water in the evening.
• In the evening, we saw a big hippo coming out of the water.

But the first version is probably the best basic translation.

The key things to notice are:

• Tu-li-mw-ona: subject + past tense + object marker + verb stem
• kiboko mkubwa: noun followed by agreeing adjective
• akitoka: a concurrent/subordinate form meaning coming out / while coming out
• kwenye maji: locative phrase
• jioni: time expression at the end

So this one sentence is useful because it shows several very common Swahili patterns at once.