Learn Hardcore Indonesian: Dia makan siang dahulu, sedangkan saya sudah makan pagi. - He/She eats lunch first, whereas I have already eaten breakfast.

Here it means first / beforehand (i.e., before another action). In everyday speech, the more common form is dulu. The meaning “long ago/formerly” also exists for dahulu, but that reading usually appears when dahulu is placed at the start of a sentence (e.g., “Formerly, …”), not after the verb phrase as here.

Is there a difference between dahulu, dulu, lebih dulu, and terlebih dahulu?

dulu: most common/colloquial for “first.”
dahulu: slightly more formal than dulu; same meaning here.
lebih dulu / terlebih dahulu: “beforehand/first” with a polite, careful tone; common in instructions or formal speech.

Does Dia makan siang dahulu refer to the past or the future?

Indonesian doesn’t mark tense by default. This can mean “(will) have lunch first” (relative to a planned action) or “had lunch earlier,” depending on context. To make it clearly future, add akan; for clearly past, add a time word like tadi (earlier today) or kemarin (yesterday). Completion can also be shown with sudah.

Where should dahulu/dulu go in the clause? Can I put it at the beginning?

For the “first/beforehand” meaning, it naturally comes after the verb phrase: makan siang dahulu/dulu. Fronting it changes the sense: Dahulu, … tends to mean “formerly/once,” not “first (before doing X).”

What exactly does sedangkan do here, and how does it differ from sementara, padahal, and tapi/namun?

sedangkan: “whereas/as for,” used to contrast two subjects/situations side by side (neutral contrast).
sementara: “while/meanwhile,” focuses on simultaneity in time.
padahal: “even though/whereas,” highlights a contradiction or something contrary to expectation.
tapi/namun: “but/however,” general contrast; not specifically side-by-side comparison.

Do I need the comma before sedangkan?

It’s standard to use a comma when sedangkan links two independent clauses. In casual writing you may see it omitted, but the comma is recommended.

What nuance does sudah add in saya sudah makan pagi? How is it different from telah, and what’s the negative?

sudah marks a completed action (“already”). telah is a more formal/written equivalent. The negative counterpart is belum (“not yet”). Don’t confuse sudah with baru, which means “just/recently.”

Is makan pagi natural, or should I say sarapan?

Both are understood. For breakfast, sarapan is more common in everyday speech than makan pagi. For lunch, makan siang is the standard; for dinner, makan malam (not usually makan sore).

Is makan siang just “verb + object,” or is it a set expression?

It behaves as a set expression meaning “to have lunch.” You don’t usually treat siang as a direct object. To mention the food, say:

Dia makan siang dengan nasi goreng, or
Dia makan nasi goreng saat makan siang, rather than “Dia makan siang nasi goreng.”

Could I use dulu instead of dahulu here?

Yes. Dia makan siang dulu, sedangkan saya sudah makan pagi is perfectly natural and more colloquial.

Can I start a sentence with sedangkan?

Yes, especially when contrasting with prior context: Sedangkan saya sudah makan pagi. That reads like “Whereas I have already had breakfast.”

Can I use sedang instead of sedangkan?

No. sedang marks the progressive aspect (“be doing”), e.g., Dia sedang makan siang (“He/She is eating lunch”). sedangkan is a conjunction meaning “whereas.”

Are there pronoun nuances with dia/ia and saya/aku?

dia: he/she (gender-neutral), common in speech and writing.
ia: he/she, preferred in formal writing and typically as a subject.
beliau: respectful “he/she” for elders/authority.
saya: polite “I.”
aku: informal “I.” So you could say: Dia makan siang dulu, sedangkan aku sudah sarapan (informal).

What time ranges do pagi and siang usually cover?

Roughly: pagi = morning (about 4–11 a.m.); siang = late morning to mid‑afternoon (about 11 a.m.–3 p.m.); then sore (late afternoon) and malam (evening/night).

Can I drop the pronouns here?

Indonesian often drops subjects when clear from context, but with sedangkan you usually keep them for contrast. You might hear something like Makan siang dulu; saya sudah sarapan, but omitting both subjects could reduce clarity.

How would I say “whereas I haven’t had breakfast yet”?

Use belum: sedangkan saya belum makan pagi or more colloquially sedangkan saya belum sarapan.