Baba alijaza dumu la maji asubuhi, halafu akaliweka nyuma ya nyumba.

alijaza can be split like this:

• a- = he / she
• -li- = past tense
• jaza = fill

So alijaza means he filled or she filled. In this sentence, because of Baba, it means he filled.

In Swahili, the verb often already tells you the subject. So alijaza by itself can mean he filled.

Baba is still included because it names who that he is. This is very normal. Swahili often uses both:

• the noun: Baba
• the subject marker in the verb: a-

So the sentence is not repetitive in a bad way; it is just clear and natural.

dumu is a container, often a jerrycan or plastic can.
dumu la maji literally means container of water or jerrycan of water.

It does not necessarily mean just any container. In many contexts, dumu suggests a fairly specific kind of portable container, often for water or fuel.

This is because Swahili uses agreement based on noun classes.

• dumu belongs to noun class 5 in the singular.
• The connector meaning of must agree with that noun.
• For class 5 singular, the form is la.

So:

• dumu la maji = jerrycan of water

If the noun were plural:

• madumu ya maji = jerrycans of water

So the connector changes with the noun class.

asubuhi means morning or in the morning, depending on context.

Swahili often does not need a separate word matching English in for time expressions. So:

• asubuhi = in the morning
• jioni = in the evening
• usiku = at night

That is very normal in Swahili.

Yes. Swahili word order is somewhat flexible, especially with time expressions.

For example, these can all sound natural depending on style and emphasis:

• Baba alijaza dumu la maji asubuhi.
• Asubuhi, Baba alijaza dumu la maji.
• Baba asubuhi alijaza dumu la maji.

The version in your sentence is a very ordinary and natural placement.

halafu means then, after that, or afterwards.

It connects one action to the next:

• first he filled the jerrycan
• halafu = then
• he put it behind the house

It is a very common sequencing word in both speech and writing.

This is one of the most important things to notice in the sentence.

akaliweka contains aka-, which is often used in narration to show the next action in sequence: and then he...

So:

• alijaza = he filled
• halafu akaliweka = then he put it

A rough breakdown is:

• a- = he
• -ka- = and then / next in sequence
• -li- = it
• weka = put / place

So akaliweka means something like and then he placed it.

The -li- in akaliweka is an object marker, meaning it.

It refers back to dumu.

This is again about noun classes:

• dumu is class 5 singular
• the object marker for that class is li

So:

• akaliweka = and then he placed it
• where it = the jerrycan

This is very common in Swahili: once the object has already been mentioned, the next verb can include an object marker referring back to it.

Yes, they both contribute the idea of sequence, but using both is still natural.

• halafu is an independent word meaning then / after that
• aka- is a verbal marker that also helps show the next action

Together they make the storytelling flow very clearly. In natural Swahili, this kind of combination is common, especially in narrative style.

It means behind the house.

Breakdown:

• nyuma = back / behind
• ya = of
• nyumba = house

Literally it is something like the back of the house, but in normal English translation it becomes behind the house.

So akaliweka nyuma ya nyumba means then he put it behind the house.

The -a connector changes form to agree with the following noun class.

nyumba belongs to the class that takes ya, so we get:

• nyuma ya nyumba = behind the house

You will see the same pattern in many expressions:

• mbele ya nyumba = in front of the house
• ndani ya nyumba = inside the house
• juu ya meza = on top of the table

So ya here is part of a very common location pattern.

It can work like both, depending on context.

• Baba can mean father
• it can also mean dad
• sometimes it can even be used as a respectful way to refer to an older man, depending on context

Since you already know the meaning of the whole sentence, the main thing to notice here is that Baba functions as the subject of the sentence.

Yes, it could, but the meaning would be a little less explicit unless the context is very clear.

• akaliweka = then he put it
• akaweka = then he put / placed

Including -li- makes it very clear that he placed the jerrycan mentioned earlier. Swahili often uses object markers this way to keep the reference smooth and clear.