Learn Hardcore Indonesian: Ibu membeli bawang merah di pasar.

ibu (lowercase) = mother (generic).
Ibu (capitalized) = often “Mother/Mom” (a specific person) or a polite form of address meaning “Ma’am/Mrs.” Because the sentence starts with a capital, context decides the meaning. To be explicit:
Ibu saya / ibuku = my mother.
Ibu itu = that lady/that mother.
As address: Ibu or shortened Bu (e.g., Bu Sari).

How do I say “my mother” clearly?

Use a possessive:

Neutral/formal: Ibu saya membeli bawang merah di pasar.
Colloquial/literary: Ibuku membeli bawang merah di pasar.

Why is there no word for “the” or “a” in Indonesian?

Indonesian has no articles. Definiteness and specificity come from context or demonstratives:

“a mother”: seorang ibu
“the/that mother/lady”: ibu itu
“this mother/lady”: ibu ini
“the shallots” (specific): bawang merah itu or bawang merahnya (context-linked “the/its”).

How do I show past, present, or future? The verb doesn’t change.

Indonesian verbs don’t conjugate for tense. Use time words/aspect markers:

Past: Ibu tadi membeli…, Ibu sudah membeli…, Kemarin Ibu membeli…
Progressive: Ibu sedang membeli… (formal), Ibu lagi beli… (informal)
Future: Ibu akan membeli…, Nanti Ibu membeli… (more natural: Nanti Ibu beli…)

What’s the difference between membeli and beli?

beli is the root “buy.”
membeli is the standard active form with the meN- prefix. In everyday speech, people often just use beli: Ibu beli bawang merah di pasar. Both mean “buy,” but membeli is more formal/complete.

How is the prefix meN- forming membeli from beli?

The active prefix meN- assimilates to the first consonant of the root:

Before b, it becomes mem-. So: meN- + beli → membeli. (Other patterns: men- before d/j/c, meng- before g/h/k/vowel, meny- before s, with certain consonants dropping.)

Why is di separate in di pasar? I’ve seen di- attached to words too.

di as a preposition (“at/in/on”) is written separately: di pasar, di rumah.
di- as a passive prefix attaches to verbs: dibeli (“is/was bought”). So: di pasar (at the market) vs dibeli (bought).

What’s the difference between di pasar and ke pasar?

di pasar = at/in the market (location).
ke pasar = to the market (direction/motion). Example: Ibu pergi ke pasar untuk membeli bawang merah.

Is bawang merah “red onions” or “shallots”?

In Indonesian usage, bawang merah usually refers to shallots (the small purple/red ones common in Indonesian cooking). For the large globe onions, Indonesians say bawang bombai (you can specify color: bawang bombai merah/kuning/putih).

How do I make it clearly singular or plural?

By default it’s unspecified. To clarify:

Singular (one unit): satu butir bawang merah
Plural (some): beberapa bawang merah
With numbers/measure: dua butir, setengah kilo, dua kilo bawang merah

What classifiers or measures are natural with bawang merah?

Common choices:

By weight: sekilo, setengah kilo, dua ons bawang merah
By piece: butir (e.g., tiga butir bawang merah) is common in recipes
By bag/bundle: sekantong/sekantong plastik (a bag of), seikat is not typical for shallots

Why is the adjective after the noun (bawang merah, not merah bawang)?

In Indonesian, adjectives typically follow the nouns they modify:

bawang merah (red/shallot onion)
pasar tradisional (traditional market)
baju baru (new shirt)

Can Ibu also mean “you” when speaking to an older woman?

Yes. As a polite second-person form, you can address a woman as Ibu/Bu:

Ibu mau beli bawang merah? = Would you like to buy shallots, Ma’am?

How do I say this as a passive sentence?

Standard passive: Bawang merah dibeli (oleh) Ibu di pasar.
Colloquial short passive (no oleh): Bawang merah dibeli Ibu di pasar. Passive shifts the focus to the object.

How do I negate the sentence?

Use tidak to negate the verb:

Ibu tidak membeli bawang merah di pasar. If you’re negating the place specifically, you can say:
Ibu membeli bawang merah bukan di pasar (melainkan di supermarket).

How do I turn it into a yes–no question?

Neutral: Apakah Ibu membeli bawang merah di pasar?
Conversational (intonation only): Ibu membeli bawang merah di pasar?
Add a tag: Ibu membeli bawang merah di pasar, ya?

How do I say “Mom bought the shallots at the market” (specific shallots)?

Use a demonstrative or the enclitic -nya:

Ibu membeli bawang merah itu di pasar.
Ibu membeli bawang merahnya di pasar. (the known/previously mentioned shallots)

Is di pasar “at” or “in” the market?

It can be either, depending on context. di covers English “at/in/on.” For physical locations, di pasar is the natural choice (not pada or dalam, unless you mean literally “inside” something enclosed).

Any quick pronunciation tips for this sentence?

bawang: final -ng is a velar nasal [ŋ], not “ngg.”
merah: the e is a schwa-like sound [ə] in many accents; final h is audible.
pasar: roll or tap the r lightly.