Learn Hardcore Indonesian: Sebuah pesan singkat dikirim kepada pelanggan lama dalam lima menit. - A short message is sent to longtime customers within five minutes.

Indonesian often uses the di- passive to focus on the thing affected and to sound formal/neutral. Here, dikirim lets you talk about the message without naming the sender.

Active alternative: (Kami/Perusahaan) mengirim sebuah pesan singkat kepada pelanggan lama (dalam lima menit). (We/The company send a short message to a long-time customer…)
Future is often inferred from context; you can add akan if you want: … akan dikirim … (will be sent).

How do I say who sent the message?

Add an agent with oleh in a passive, or switch to active:

Passive with agent: Sebuah pesan singkat dikirim oleh tim kami kepada pelanggan lama dalam lima menit. (…sent by our team…)
Active: Tim kami mengirim sebuah pesan singkat kepada pelanggan lama dalam lima menit.

What’s the difference between dikirim, dikirimkan, and terkirim?

dikirim: generic passive of “send.” Neutral and common.
dikirimkan: passive with -kan; often a bit more formal and naturally used with a stated recipient (e.g., … dikirimkan kepada …).
terkirim: result/state or unintentional sense; in messaging UIs it means “sent/delivered.” Example: Pesan Anda sudah terkirim. (Your message has been sent.)

What’s the difference among mengirim, mengirimkan, and mengirimi?

mengirim [thing] (ke/kepada [recipient]): basic “send.” Example: Kami mengirim pesan kepada pelanggan.
mengirimkan [thing] (kepada [recipient]): emphasizes the thing sent; common/formal. Example: Kami mengirimkan pesan kepada pelanggan.
mengirimi [recipient] [thing]: -i puts the recipient as the direct object. Example: Kami mengirimi pelanggan itu pesan.
Tip: If you want to drop the preposition before the recipient, use mengirimi.

Is sebuah necessary before pesan singkat?

No. Indonesian doesn’t require an article. All are possible:

Pesan singkat dikirim … (most neutral)
Sebuah pesan singkat dikirim … (emphasizes “one item”)
Satu pesan singkat … (numeral “one”; can sound counting/precise)
Suatu pesan singkat … (“a certain/particular” message; adds a hint of specificity/unknown identity)

Does pesan singkat specifically mean an SMS/text?

Literally “short message.” In many contexts it implies an SMS or brief text message. Alternatives:

SMS (still common), pesan teks, or platform-specific pesan WhatsApp.
In formal writing, pesan singkat is safe and technology-agnostic.

Why is the adjective after the noun (pesan singkat) and not before?

Indonesian descriptive adjectives usually follow the noun: pesan singkat (short message), pelanggan lama (long-time customer). Some fixed modifiers come before (e.g., mantan former, para plural marker, sang/si titles).

Does pelanggan lama mean an elderly customer, a long-time customer, or a former customer?

pelanggan lama = a long-time/longstanding customer (duration of relationship).
pelanggan tua = an old/elderly customer (age).
mantan pelanggan = a former/ex-customer (no longer a customer). You can clarify duration with pelanggan yang sudah lama (berlangganan).

Is pelanggan here singular or plural? How can I make it explicit?

Unmarked nouns can be singular or plural. To specify:

Singular human: seorang pelanggan lama (one long-time customer).
Plural humans: para pelanggan lama (long-time customers).
Reduplication (pelanggan-pelanggan) is possible but para is more natural for people.

Should it be kepada, ke, or untuk for the recipient?

kepada: to (a person/party). Formal/standard: … kepada pelanggan …
ke: to (general direction/place); in speech it can also mark recipients: … ke pelanggan … (more casual).
untuk: for (intended for), not the act of sending. Use it for purpose: pesan untuk pelanggan (a message for customers), but with “send,” prefer kepada/ke.

What exactly does dalam lima menit mean here—within five minutes, in five minutes from now, or for five minutes?

By default, dalam lima menit = within a five‑minute window or it takes five minutes. To disambiguate:

Within five minutes (deadline): paling lambat lima menit / dalam waktu lima menit.
In five minutes from now: lima menit lagi / dalam lima menit lagi.
For five minutes (duration of an activity): selama lima menit.

Where can I place the time phrase?

Start or end are both fine:

End (neutral): … dikirim … dalam lima menit.
Fronted (for emphasis/context): Dalam lima menit, sebuah pesan singkat dikirim …

How do I make the tense/aspect clear (past vs future)?

Indonesian relies on particles/adverbs:

Past/result: sudah/telah (already) – Pesan singkat sudah dikirim.
Future: akan (will) – Pesan singkat akan dikirim.
Ongoing: sedang (in progress) – Pesan sedang dikirim.

How can I rephrase the sentence to focus on the recipient (An old customer was sent a short message…)?

Use the passive with -i (recipient as subject):

Seorang pelanggan lama dikirimi sebuah pesan singkat (dalam lima menit).
This highlights the customer rather than the message.

Can I avoid using a preposition before the recipient?

Yes, with mengirimi:

Kami mengirimi pelanggan lama itu pesan singkat. (We sent that long-time customer a short message.) With mengirimkan, keep kepada: Kami mengirimkan pesan singkat kepada pelanggan lama itu.

Any small tweaks to make the sentence sound especially natural in formal use?

Drop the article unless you need “one”: Pesan singkat akan dikirim kepada para pelanggan lama dalam waktu lima menit.
If there’s a hard deadline: Pesan singkat akan dikirim kepada para pelanggan lama paling lambat lima menit lagi.
If the sender matters: Pesan singkat akan dikirim oleh tim layanan kami kepada para pelanggan lama dalam waktu lima menit.