Mtoto alicheka alipomwona nyani akiruka kwenye tawi.

It has a main clause and a time clause:

• Mtoto alicheka = The child laughed
• alipomwona nyani akiruka kwenye tawi = when he/she saw the monkey jumping on/onto a branch

So the overall pattern is:

[main action] + [when-clause explaining what caused it]

Alicheka can be divided like this:

• a- = he/she
• -li- = past tense
• -cheka = laugh

So alicheka means he/she laughed.

Because mtoto is a singular animate noun, the verb uses the singular subject marker a-.

A useful breakdown is:

• a- = he/she
• -li- = past
• -po- = when
• mw- / m- = object marker for a singular animate object, him/her/it
• -ona = see

So alipomwona means roughly when he/she saw him/it.

In this sentence, that object marker refers to nyani.

That is a very common learner question.

In Swahili, an object marker can appear on the verb even when the full object noun is also stated. This is especially common when the object is:

• animate
• specific
• already important in the conversation

So alipomwona nyani is natural and means something like when he/she saw the monkey.

You may also hear alipoona nyani, without the object marker. That is also possible, but alipomwona nyani can sound a bit more specific or more focused on that monkey.

Akiruka breaks down as:

• a- = he/she/it for a singular animate subject
• -ki- = while/as
• -ruka = jump

So akiruka means while it was jumping, as it jumped, or simply jumping depending on how you translate it into English.

The most natural reading is that the monkey is doing the jumping.

That is because akiruka comes right after nyani, so it describes nyani:

• nyani akiruka = the monkey jumping / the monkey as it was jumping

So the sentence means that the child laughed when he/she saw the monkey jumping.

Even though nyani does not look like a typical m-/wa- noun, it refers to an animate being, so Swahili normally uses animate agreement with it.

That is why you get:

• singular: nyani akiruka = the monkey is jumping
• plural: nyani wakiruka = the monkeys are jumping

So the a- in akiruka shows singular animate agreement.

Here -ki- marks an action happening at the same time as another action. It often means:

• while
• as
• when in the process of

So nyani akiruka is basically the monkey while jumping or the monkey as it was jumping.

This is a very common way in Swahili to express simultaneous action.

• kwenye is a locative word that can mean on, in, at, or sometimes to/onto, depending on context
• tawi = branch

So kwenye tawi can be understood as:

• on a branch
• onto a branch
• sometimes simply at the branch, depending on the situation

In this sentence, on a branch or onto a branch is the most natural English rendering.

Swahili does not use articles the way English does. There is no direct equivalent of a or the in ordinary noun phrases.

So:

• mtoto can mean a child or the child
• nyani can mean a monkey or the monkey

The exact meaning depends on context, not on an article.

No. Mtoto just means child.

Also, the verb marker a- means he/she without distinguishing gender. Swahili third-person singular does not mark he versus she.

So from this sentence alone, we do not know whether the child is male or female.

Here it is singular.

A tricky point is that nyani often looks the same in singular and plural. What tells you the number is the agreement on the verb or modifier.

In this sentence, akiruka has singular agreement a-, so it means one monkey.

If it were plural, you would expect something like:

• nyani wakiruka = monkeys jumping

Yes. Because Swahili does not have articles, English translators must choose between a and the from context.

So depending on the situation, this sentence could be rendered as either:

• The child laughed when he/she saw the monkey jumping on a branch
• The child laughed when he/she saw a monkey jumping on a branch

Both are structurally possible from the Swahili alone.