Mtoto alitulia baada ya bibi kumbembeleza.

Here is a word-by-word breakdown:

• Mtoto = child
• alitulia = calmed down / became quiet / settled
• baada ya = after
• bibi = grandmother or sometimes old woman, depending on context
• kumbembeleza = to soothe / coax / comfort him or her

So the whole sentence means something like:

The child calmed down after grandmother soothed him or her.

Alitulia can be broken into:

• a- = subject marker for a singular person or class 1 noun
• -li- = past tense
• tulia = be calm, settle down, become quiet

So alitulia literally means he/she became calm. Since the subject is mtoto, it means the child calmed down.

Because mtoto belongs to the human singular noun class, often called class 1.

In Swahili, verbs agree with the noun class of the subject. For a singular human noun like mtoto, the usual subject marker is a-.

For example:

• Mtoto alitulia = The child calmed down
• Watoto walitulia = The children calmed down

So:

• mtoto → a-
• watoto → wa-

Not by itself. Mtoto simply means child, and it does not tell you whether the child is male or female.

That is why English may translate the object in kumbembeleza as him or her, unless the wider context makes the gender clear.

Baada ya means after.

It is commonly followed by:

• a noun: baada ya kazi = after work
• an infinitive verb: baada ya kula = after eating
• a noun plus an infinitive phrase: baada ya bibi kumbembeleza = after grandmother soothing/comforting him or her, which English naturally says as after grandmother soothed him or her

So in this sentence, baada ya introduces the event that happened first.

After baada ya, Swahili often uses an infinitive-style verb rather than a fully finite past-tense verb.

So:

• kumbembeleza = to soothe him/her
• baada ya bibi kumbembeleza = literally something like after grandmother soothing him/her

English usually turns that into a normal past clause:

after grandmother soothed him/her

So even though English wants a full past-tense verb, Swahili often prefers this infinitive construction after baada ya.

Kumbembeleza can be broken down as:

• ku- = infinitive marker, like to
• m- = object marker meaning him/her
• bembeleza = soothe, coax, cajole, comfort

So kumbembeleza means to soothe him/her.

The spelling looks like one long word because Swahili usually writes these parts together.

The m- refers to a singular human object, in this case the child.

Since mtoto is a singular human noun, the object marker is m-:

• kumbembeleza = to soothe him/her
• kuwabembeleza = to soothe them

So the sentence tells us that bibi soothed the child.

Because Swahili often puts object pronouns inside the verb itself.

In English, you would say:

• grandmother soothed him
• grandmother soothed her

In Swahili, that object can be built into the verb:

• kum-bembeleza = to soothe him/her

So the m- already carries the meaning of him/her.

Because the object marker m- already points back to mtoto, so repeating the noun is not necessary.

Swahili often avoids repeating a noun when the reference is clear from the verb.

So this is enough:

• bibi kumbembeleza = grandmother soothing him/her

The listener understands that him/her refers to mtoto.

Not always. Bibi can mean:

• grandmother
• old woman
• sometimes a respectful way of addressing an older woman

In this sentence, the most natural meaning is grandmother, but the exact sense depends on context.

Swahili usually does not use articles like the or a/an.

So:

• mtoto can mean a child or the child
• bibi can mean a grandmother, the grandmother, or simply grandmother

Context tells you which one is meant.

Mostly, yes.

The main structure is:

• Mtoto alitulia = The child calmed down
• baada ya bibi kumbembeleza = after grandmother soothed him/her

So the sentence follows a pattern close to:

Subject + verb + after-clause

That said, the internal structure of the after phrase is more Swahili-like, because it uses an infinitive form rather than the kind of full clause English usually prefers.

Yes. For example, you could move the after phrase to the front:

• Baada ya bibi kumbembeleza, mtoto alitulia.

This means the same thing:

After grandmother soothed him or her, the child calmed down.

Swahili allows this kind of rearrangement, just like English does.