Ibu membersihkan genangan itu bukan karena halaman terlihat kotor, melainkan karena dia khawatir nyamuk datang lagi.

Ibu can mean several things depending on context:

• mother / mom
• Mrs. / ma’am
• a respectful way to refer to an adult woman

In this sentence, Ibu most naturally means Mother/Mom if it appears in a family context. But in another context, it could also refer to the woman / Mrs. X.

So the exact English translation depends on who Ibu is in the situation.

Membersihkan is the active verb to clean.

It comes from:

• bersih = clean
• -kan = a suffix that often helps form a verb meaning to make something become X or to do X to something
• meN- = an active verb prefix

So:

• bersih = clean
• membersihkan = to clean something

Because the sentence has a direct object, genangan itu (that puddle / that standing water), the active transitive verb membersihkan fits naturally.

Compare:

• Halamannya bersih. = The yard is clean.
• Ibu membersihkan halaman. = Mother cleaned the yard.

Genangan usually refers to a pool of standing water, a puddle, or water that has collected somewhere.

It comes from the root genang, which relates to water gathering or pooling.

So genangan itu is not just any water in general. It specifically suggests:

• water that has collected
• water that is staying there
• standing water

That is important because the second half of the sentence mentions mosquitoes, and standing water is where mosquitoes breed.

In Indonesian, demonstratives like ini (this) and itu (that) usually come after the noun.

So:

• genangan itu = that puddle / that standing water
• halaman itu = that yard
• nyamuk itu = that mosquito

This is normal Indonesian word order.

English: that puddle
Indonesian: genangan itu

This pattern means:

• not because ..., but rather because ...

In the sentence:

• bukan karena halaman terlihat kotor
• melainkan karena dia khawatir nyamuk datang lagi

the speaker is correcting a possible assumption.

So the structure is:

• bukan karena X
• melainkan karena Y

= not because of X, but because of Y instead

This is a fairly formal or polished contrastive structure. It strongly sets up the real reason after rejecting another reason.

This is a very common learner question.

A useful rule of thumb is:

• tidak negates verbs and adjectives
• bukan negates nouns, noun-like elements, and is also commonly used in contrasts like bukan ..., melainkan ...

Here, bukan karena ... melainkan karena ... is a fixed and natural contrast pattern.

So:

• bukan karena X, melainkan karena Y = not because of X, but rather because of Y

Using tidak here would sound unnatural in this structure.

Melainkan means something like:

• but rather
• instead
• rather

It is often used after a negative statement, especially after bukan.

So:

• bukan karena X, melainkan karena Y

is more precise than simply saying:

• bukan karena X, tetapi karena Y

Both may be understandable, but melainkan is especially suited to correcting or replacing the first explanation with the second one.

It has the sense of:

• not X — rather, Y

Terlihat means looks, appears, or is seen as.

So:

• halaman terlihat kotor = the yard looks dirty / appears dirty

Here, terlihat describes appearance, not necessarily objective fact. The yard may simply seem dirty.

A few similar words are:

• terlihat = appears, is visible as
• tampak = appears, seems
• kelihatan = looks, appears (often more conversational)

So this sentence could have used another word, but terlihat is perfectly natural.

Indonesian often does not use a verb equivalent to English to be in the present tense.

So:

• dia khawatir = she is worried
• halaman kotor = the yard is dirty
• halaman terlihat kotor = the yard looks dirty

This is normal Indonesian grammar. English requires is, but Indonesian usually does not.

Khawatir is often best understood as an adjective/state word meaning worried.

So:

• dia khawatir = she is worried

In Indonesian, words expressing states often work directly as predicates without to be.

That said, in practice, learners may feel that khawatir behaves a bit like a verb in translation because English says she worries / she is worried. But grammatically in Indonesian, it is very commonly treated as a state/adjective-like predicate.

In Indonesian, the conjunction bahwa can mean that, but it is often omitted when the meaning is already clear.

So:

• dia khawatir nyamuk datang lagi

literally looks like:

• she worried mosquitoes come again

but naturally means:

• she is worried (that) mosquitoes will come again

The omitted that is very common and natural.

You could say:

• dia khawatir bahwa nyamuk datang lagi

but that is usually less natural in everyday speech here.

Datang means come or arrive.
Lagi means again.

So:

• nyamuk datang lagi = mosquitoes come again / mosquitoes come back again

In English, we might say:

• the mosquitoes will come back again
• mosquitoes will return
• mosquitoes will show up again

But Indonesian very naturally uses datang even for things like insects arriving.

Because the sentence is about standing water, the idea is that the water may attract mosquitoes again.

Here, lagi clearly means again.

So:

• nyamuk datang lagi = mosquitoes come again

In other contexts, lagi can sometimes relate to an ongoing action or combine with other words in different ways, but in this sentence the meaning is straightforwardly again.

Indonesian often allows subjects to be omitted when they are obvious, but keeping dia here makes the sentence clearer.

So:

• melainkan karena dia khawatir nyamuk datang lagi

clearly tells us whose worry it is.

If the subject were omitted, the sentence might still be understandable from context, but dia helps avoid ambiguity.

In this sentence, dia most naturally refers back to Ibu.

So the meaning is:

• Mother cleaned the standing water not because the yard looked dirty, but because she was worried mosquitoes would come again.

Indonesian uses dia for he or she, so gender is not marked in the pronoun itself. You understand it from context.

Yes. Lagi often suggests repetition.

So datang lagi implies:

• mosquitoes came before
• and she is worried they will come again

That fits well with the mention of standing water, which can repeatedly attract mosquitoes.

Not always exactly. Halaman can mean:

• yard
• courtyard
• front yard
• outdoor area around a house
• grounds/space in front of a building

So yard is a good translation here, but the exact English word depends on the physical setting.

Indonesian often does not mark future tense explicitly if the context already makes it clear.

So:

• dia khawatir nyamuk datang lagi

naturally means:

• she is worried mosquitoes will come again

Even though there is no separate word for will, the meaning is understood from the context of worry.

If needed, Indonesian could make it more explicit with words like akan, but it is not necessary here:

• dia khawatir nyamuk akan datang lagi

This is possible, but the original sentence is already natural.

It sounds mostly neutral to slightly formal.

A few things that make it feel a bit more polished are:

• melainkan
• terlihat

In everyday casual speech, someone might choose slightly simpler alternatives, but this sentence is perfectly natural and good standard Indonesian.