Learn Hardcore Indonesian: Kupon itu belum kedaluwarsa; saya telah mengeceknya di aplikasi. - That coupon hasn’t expired; I have checked it in the app.

In Indonesian, demonstratives typically follow the noun. Kupon itu means “that coupon” or “the (aforementioned) coupon.” It points to a specific, known coupon. Without itu, kupon is more general (“a coupon” in context).

Could I use ini instead of itu?

Yes, but the meaning changes. Kupon ini = “this coupon” (near the speaker or just introduced). Kupon itu = “that coupon” (farther away, or the one already known/previously mentioned). In discourse, itu often functions like “the.”

Why is it belum and not tidak?

Belum means “not yet,” implying the situation may change later. Tidak is a simple negation (“not”). Here, belum kedaluwarsa = “hasn’t expired yet.” Using tidak kedaluwarsa would sound odd or absolute (“is not expired” as a general truth), which isn’t the intended idea.

Is belum kedaluwarsa the same as masih berlaku?

They’re close:

Belum kedaluwarsa = “not expired yet” (focus on the expiry status).
Masih berlaku = “still valid” (focus on validity). Both are fine; choose based on what you want to emphasize.

Is the spelling kedaluwarsa correct? I’ve seen kadaluarsa/kadaluwarsa too.

The standard dictionary form (KBBI) is kedaluwarsa. Variants like kadaluarsa are extremely common in everyday use and widely understood. In formal writing, prefer kedaluwarsa.

Is kedaluwarsa a verb or an adjective? How do I say “it expired”?

Kedaluwarsa is primarily an adjective meaning “expired.” To say “it expired,” Indonesian often uses aspect markers:

Kupon itu sudah kedaluwarsa = “The coupon has expired.” For the event of expiring, you can say:
Masa berlakunya sudah berakhir = “Its validity period has ended.”
Kupon itu kedaluwarsa kemarin = “The coupon expired yesterday” (adjectival predicate with a time expression).

What does the semicolon do here? Could I use something else?

The semicolon links two closely related independent clauses. It’s correct but less common in everyday Indonesian. You could also use:

A period: Kupon itu belum kedaluwarsa. Saya telah mengeceknya di aplikasi.
A connector: Kupon itu belum kedaluwarsa, karena saya sudah mengeceknya di aplikasi.

Why telah instead of sudah?

Both mark completed action. Telah is more formal/literary; sudah is more common in speech. The sentence sounds slightly formal. Colloquially: Saya sudah mengeceknya di aplikasi.

Can I drop the prefix and say Saya sudah cek di aplikasi?

Yes, that’s very natural in casual speech. Options from most casual to most formal:

Saya sudah cek di aplikasi.
Saya sudah mengecek di aplikasi.
Saya telah mengecek di aplikasi.

What does the -nya in mengeceknya mean?

It’s the third-person enclitic pronoun (“it/him/her/their”), here meaning “check it.” Saya telah mengeceknya = “I have checked it.” It refers back to kupon and avoids repeating the noun. You could also say Saya telah mengecek kupon itu.

Could -nya be ambiguous? Might it refer to the app?

In theory, yes: -nya can refer to any salient third-person referent. Context normally makes it clear (here, the coupon). If there’s any chance of confusion, repeat the noun: Saya sudah mengecek kupon itu di aplikasi.

Is it correct to attach -nya directly to the verb like this?

Yes. Enclitic -nya attaches directly to the verb: membacanya, melihatnya, mengeceknya. No hyphen is needed.

Why is it mengecek and not something like mencek?

The base cek is monosyllabic. With the prefix meN-, monosyllabic bases typically take menge-: mengecek. This is a regular morphophonemic pattern (compare: mengecat from cat “to paint”).

Is mengecek different from memeriksa?

They overlap. Mengecek (cek) = “to check/verify” (everyday, tech/business contexts). Memeriksa (periksa) = “to examine/inspect” (more formal or thorough, e.g., doctors, audits). In this sentence, both work: Saya sudah mengeceknya/ memeriksanya di aplikasi.

Is di aplikasi the right preposition? What about pada, melalui, or di dalam?

di aplikasi = “in/on the app” (common and natural).
pada aplikasi = more formal/stiff; less used in this context.
melalui/lewat aplikasi = “through the app” (emphasizes the medium).
di dalam aplikasi = “inside the app” (adds physical/inside nuance; often unnecessary). Also remember: di (preposition) is written separately: di aplikasi, not “diaplikasi.”

Could I omit itu and just say Kupon belum kedaluwarsa?

You could, but it sounds less specific, as if talking about coupons in general. Kupon itu signals a particular coupon already known in context.

Would Kuponnya belum kedaluwarsa be okay?

Yes. -nya can mark definiteness (“the coupon”) or possession (“his/her/their coupon”). Without a clear possessor, listeners usually interpret it as “the (aforementioned) coupon.” Use kuponnya if the context already identifies which coupon.

Is the whole sentence formal or informal? How would a casual version look?

As written (with telah and a semicolon), it leans formal/written. Natural casual options:

Kuponnya belum kadaluarsa; gue udah cek di aplikasi. (very informal, Jakarta flavor)
Kupon itu belum kadaluarsa. Aku sudah cek di aplikasi. (neutral informal) For standard but conversational: Kupon itu belum kedaluwarsa; saya sudah mengeceknya di aplikasi.

Should it be “in the app” or “on the app” in English? Does that affect Indonesian?

In English, “in the app” is more common. Indonesian uses di for both “in/on,” so di aplikasi covers both; you don’t need to distinguish.

Any quick pronunciation tips for the tricky words?

kedaluwarsa: roughly “kuh-dah-loo-WAR-sah” (rolled/flapped r; stress commonly falls near “WAR”).
mengeceknya: “muh-NEH-chek-nyah.”
aplikasi: “ah-plee-KAH-see.”