Learn Hardcore Indonesian: Dua mangkuk kecil dan dua gelas besar dibersihkan dulu. - Two small bowls and two large glasses are cleaned first.

Here dulu means “first / before anything else / for now.” It’s about sequence, not time. It does not mean “used to” or “formerly” in this position. Synonyms: lebih dulu or the more formal terlebih dahulu; dahulu is formal/literary. In casual requests, dulu also softens the tone: “Let’s clean these first (if that’s okay).”

Why is the passive dibersihkan used instead of an active form?

Indonesian often uses the passive (prefix di-) to focus on the thing affected and to leave the agent unspecified, especially in instructions. Dibersihkan = “be/get cleaned.” Using passive here sounds natural when you’re describing a step in a process. The active would be membersihkan (“to clean something”), e.g., Seseorang membersihkan… or Saya membersihkan…

How do I say who is doing the cleaning?

You have three common options:

Passive with an agent: … dibersihkan dulu oleh petugas. (by the staff). With 1st/2nd person, this sounds a bit stiff: oleh saya/kamu is grammatical but not preferred.
“Short passive” (very natural with pronoun agents): Dua mangkuk kecil dan dua gelas besar saya bersihkan dulu.
Active: Saya membersihkan dua mangkuk kecil dan dua gelas besar dulu.

Where do adjectives go? Why is it mangkuk kecil and gelas besar (adjective after the noun)?

In Indonesian, adjectives typically follow the noun: mangkuk kecil (small bowl), gelas besar (large glass). If you say dua mangkuk yang kecil, you’re picking out “the two bowls that are small” (more selective/contrastive). For a simple description, no yang is needed.

Do I need to mark plural on mangkuk and gelas?

No. Nouns generally don’t change for plural. The numeral dua already shows plurality. You could use reduplication (mangkuk-mangkuk kecil) to mean “small bowls (in general/various),” but with a specific number, reduplication is not used.

Do I need a classifier like buah (e.g., dua buah mangkuk)?

It’s optional. Dua mangkuk kecil and dua gelas besar are perfectly natural. You can add the generic classifier buah for emphasis or clarity: dua buah mangkuk kecil, dua buah gelas besar, but many speakers omit it in everyday speech.

Could dua gelas besar mean “two big glasses of [something]”?

Only if it’s followed by what’s inside: dua gelas besar air/kopi/teh = two big glasses of water/coffee/tea. By itself, dua gelas besar refers to the objects (glasses). Here, the verb dibersihkan clearly points to the container objects being cleaned.

Can I move dulu to a different position?

End position (as in the sentence) is the most common for the meaning “first”: … dibersihkan dulu.
After the subject phrase is also fine: Dua mangkuk kecil dan dua gelas besar dulu dibersihkan (slightly different rhythm/emphasis).
Initial Dulu usually means “formerly/in the past”: Dulu dibersihkan… can be read as “In the past, (they) were cleaned…,” so avoid this if you mean “first.”
More formal: terlebih dahulu can go before or after the verb: … terlebih dahulu dibersihkan / … dibersihkan terlebih dahulu.

Is di attached or separated in dibersihkan?

Attach it: dibersihkan. The prefix di- forms the passive and must join the verb. Don’t write di bersihkan. The spaced di is a preposition meaning “at/in/on,” e.g., di rumah (at home).

Why does the verb end with -kan?

The base is the adjective bersih (clean). To make a transitive verb “clean (something),” Indonesian uses meN- … -kan → membersihkan. The passive keeps -kan: dibersihkan. Without -kan here would be ungrammatical. A simpler verb with a similar meaning is dicuci (“washed”).

How do I express different tenses/aspects with this sentence?

Indonesian uses particles:

Future: … akan dibersihkan dulu (will be cleaned first).
Progressive: … sedang dibersihkan (dulu) (are being cleaned [first]).
Completed: … sudah dibersihkan (dulu) (have been cleaned [first]).
Note: dulu is about sequence; you can keep or drop it depending on context.

Is there a more colloquial way to say this?

Yes, in informal Jakarta-style Indonesian:

Passive colloquial: … dibersihin dulu (using the -in ending).
Short passive: … saya bersihin dulu.
Very casual with a different verb: … diberesin dulu (“tidied up first”).
Choose based on the setting; the original is neutral and widely appropriate.

Can I say mangkuk kecil dua and gelas besar dua?

That order (noun + adjective + number) is common in quick, telegraphic contexts (ordering, listing): mangkuk kecil dua, gelas besar dua. In full sentences, the standard is numeral first: dua mangkuk kecil, dua gelas besar.

Do I need to repeat dua before gelas?

Yes, if you mean two of each: dua mangkuk kecil dan dua gelas besar… If you say dua mangkuk kecil dan gelas besar…, only the bowls are clearly “two”; the glasses would be understood as singular unless context forces plural.