Learn Hardcore Indonesian: Adik perempuan saya alergi susu. - My younger sister is allergic to milk.

Indonesian doesn’t need a linking verb with adjectives or stative predicates. In this sentence, alergi functions like “is allergic,” so Adik perempuan saya alergi susu literally reads “My younger sister allergic milk.” You generally use adalah only to link two nouns (e.g., Adik perempuan saya adalah perawat = “My younger sister is a nurse”), not with adjectives like “alergic.”

Why does the possessive pronoun come after the noun (adik perempuan saya) instead of before it?

Indonesian puts the possessor after the thing possessed: adik perempuan saya = “my younger sister.” Alternatives:

With a clitic: adik perempuanku (more informal).
Without specifying gender: adikku = “my younger sibling.” Note: Using the clitic, it’s natural to attach it to the end of the phrase: adik perempuanku.

Does “adik” mean “little sister”? What exactly does it imply?

Adik means “younger sibling” (younger than the speaker), regardless of gender. It’s about relative age, not size. To specify female, add perempuan: adik perempuan. For an older sibling, use kakak (then specify gender if needed).

Can I just say “adik saya alergi susu”?

Yes. Adik saya alergi susu means “My younger sibling is allergic to milk,” without specifying gender. If the gender matters, add perempuan or laki-laki.

How do I say “younger brother” instead?

Use adik laki-laki: Adik laki-laki saya alergi susu. Informally you might hear adik cowok saya, but it’s casual.

Why “perempuan” and not “wanita,” “cewek,” or “gadis”?

perempuan: neutral, common in general use and family terms (best here).
wanita: more formal/official; uncommon in kin terms like this.
cewek: slang/informal (“girl/chick”); e.g., adik cewek saya in casual speech.
gadis: “maiden/young unmarried woman,” not used for “sister” terms.

Is “alergi” a noun or an adjective in Indonesian?

It can act as both:

Adjective (stative): Dia alergi susu = “She’s allergic to milk.”
Noun: Dia punya alergi terhadap susu or Dia mengalami alergi susu = “She has a milk allergy.” The stative/adjective use is most common in everyday speech.

Do I need a preposition like “to” (“allergic to”)?

Not necessarily. Alergi susu is natural. Options:

Neutral: alergi susu
Formal: alergi terhadap susu
Also acceptable: alergi pada susu
Colloquial: alergi sama susu All mean “allergic to milk,” with register differences only.

How do I make it negative (“not allergic”)?

Use tidak with adjectives: Adik perempuan saya tidak alergi susu. Don’t use bukan here; bukan negates nouns/nominal predicates (e.g., Dia bukan dokter).

How do I ask, “Is my younger sister allergic to milk?”

Neutral/formal: Apakah adik perempuan saya alergi susu?
Conversational: Adik perempuan saya alergi susu? (rising intonation)
Casual tag: Adik perempuan saya alergi susu, ya?

How do I express the plural “my younger sisters are allergic to milk”?

Use reduplication for plural:

Adik-adik perempuan saya alergi susu. You can also say adik-adik saya yang perempuan alergi susu to make the “female ones” explicit.

What if I want to emphasize “the younger sister who is allergic to milk”?

Use yang to form a restrictive clause:

Adik perempuan saya yang alergi susu tinggal di Bandung. = “My younger sister who is allergic to milk lives in Bandung.” If you mean a specific one you both know, you can add itu:
Adik perempuan saya itu alergi susu. = “That younger sister of mine is allergic to milk.”

Can I rephrase it as “I have a younger sister who is allergic to milk”?

Yes: Saya punya adik perempuan yang alergi susu. This structure foregrounds possession (“I have…”).

Any pronunciation tips for this sentence?

adik: a-dik; final k is often unreleased (a short, crisp stop).
perempuan: pe-rem-pu-an (four syllables); the r is lightly tapped.
saya: sa-ya.
alergi: a-ler-gi (g is a hard g).
susu: su-su (both u as in “food”).

Is the register here formal or informal? Can I make it more casual?

With saya, it’s neutral to polite. More casual variants:

Adik perempuan aku alergi susu.
Jakarta slang: Adik perempuan gue alergi susu or even Adik cewek gue alergi susu (very informal).

If I mean cow’s milk specifically or dairy products, how do I say that?

Cow’s milk: susu sapi → Adik perempuan saya alergi susu sapi.
Dairy products: produk susu or olahan susu → …alergi produk/olahan susu.

How would I say “My younger sister is lactose intolerant,” not allergic?

More formal/medical: Adik perempuan saya mengalami intoleransi laktosa. Everyday phrasing is often looser, e.g., Adik perempuan saya nggak cocok sama susu or nggak bisa minum susu (meaning milk doesn’t agree with her).