Learn Hardcore Indonesian: Masalah iklim global dibahas di perpustakaan. - The issue of global climate is discussed in the library.

So masalah iklim global is literally problem [of] climate global, which we would phrase in English as the global climate problem / the problem of global climate.

Why does Indonesian say masalah iklim global and not global climate problem (with global first) like in English?

In Indonesian, the head noun usually comes first, and the modifiers (adjectives or other nouns) follow it.

Head noun: masalah (problem)
Modifier 1: iklim (climate)
Modifier 2: global (global)

So the structure is:

masalah (problem) + iklim (climate) + global (global)

In English, we often put adjectives first: global climate problem.
In Indonesian, the more natural order is: problem climate global → masalah iklim global.

What is the base verb of dibahas, and what does it mean?

The base verb is bahas.

bahas = to discuss, to talk about (in a somewhat formal or serious way)
dibahas = di- (passive prefix) + bahas (discuss)
→ is discussed / is being discussed / was discussed, depending on context.

What does the prefix di- in dibahas do?

The prefix di- forms a passive verb.

bahas = discuss (active base form)
dibahas = be discussed (passive)

So:

Active: Mereka membahas masalah iklim global.
= They discuss the global climate issue.
Passive: Masalah iklim global dibahas.
= The global climate issue is discussed.

In the passive, the object becomes the subject/topic, and the doer can be omitted or added with oleh.

Who is doing the discussing in Masalah iklim global dibahas di perpustakaan? Where is the “by someone”?

The doer (agent) is not mentioned in this sentence. That’s very common in Indonesian passive sentences.

If you wanted to include the agent, you would usually use oleh:

Masalah iklim global dibahas oleh para mahasiswa di perpustakaan.
= The global climate issue is discussed by the students in the library.

So the original sentence implies “by someone” (students, people, participants, etc.), but leaves it out because it’s not important or is understood from context.

Is the di in dibahas the same as the di in di perpustakaan?

They are different:

di- in dibahas
- A prefix attached to a verb
- Marks passive voice
- Written joined to the verb: dibahas, ditulis, dibuat.
di in di perpustakaan
- A preposition meaning in / at / on
- Used before a place noun
- Written separately: di rumah, di kantor, di perpustakaan.

So:

dibahas = be discussed (passive verb)
di perpustakaan = in/at the library (prepositional phrase of place)

How do you know whether the sentence is present, past, or future? There is no tense on dibahas, right?

Correct—Indonesian verbs do not change form for tense.
Dibahas can mean:

is discussed / is being discussed (present)
was discussed (past)
will be discussed (future, in the right context)
is discussed (in general, regularly)

The tense is understood from context or from time expressions, for example:

Kemarin, masalah iklim global dibahas di perpustakaan.
= Yesterday, the global climate issue was discussed in the library.
Besok, masalah iklim global akan dibahas di perpustakaan.
= Tomorrow, the global climate issue will be discussed in the library.
Sering, masalah iklim global dibahas di perpustakaan.
= The global climate issue is often discussed in the library.

If I want to emphasize “is being discussed right now”, where can I put sedang?

Use sedang before the verb to show an action in progress:

Masalah iklim global sedang dibahas di perpustakaan.
= The global climate issue is being discussed in the library (right now).

The neutral and most common position is:

[subject] + sedang + [verb] + [other info]
Masalah iklim global sedang dibahas di perpustakaan.

Why isn’t there a word like “is” in is discussed? Why not Masalah iklim global adalah dibahas?

In Indonesian:

You do not use adalah before a verb.
The verb itself works as the predicate without an extra “is/are”.

So:

Masalah iklim global dibahas di perpustakaan.
= The global climate issue is discussed in the library.

Adalah is mainly used for equations / definitions, where both sides are nouns or noun phrases:

Masalah iklim global adalah tantangan besar.
= The global climate issue is a big challenge.

But with verbs like dibahas, datang, membaca, you don’t add adalah.

Does Masalah iklim global mean “the global climate issue” or “a global climate issue”? How do you show the vs a in Indonesian?

Indonesian has no articles like a/an/the, so masalah iklim global can be:

the global climate issue
a global climate issue
global climate issues (in the right context)

You show “the” or “that specific one” by adding itu (that):

Masalah iklim global itu dibahas di perpustakaan.
= That global climate issue / the global climate issue is discussed in the library.

You can show “one (single) problem” roughly like a with sebuah (for inanimate, countable things):

Sebuah masalah iklim global dibahas di perpustakaan.
= A global climate issue is discussed in the library.

But often, no article is used, and context decides the meaning.

What exactly does di perpustakaan mean — “in the library” or “at the library”? Is there a difference?

Di perpustakaan can be translated as either in the library or at the library, depending on what sounds more natural in English.

di = in / at / on (general preposition for location)
perpustakaan = library

Indonesian di doesn’t sharply distinguish between in and at the way English does. Context and natural English usage decide which translation is better.

Can I change the word order to Di perpustakaan, masalah iklim global dibahas? Is that still correct?

Yes, that is correct and natural.

Masalah iklim global dibahas di perpustakaan.
Di perpustakaan, masalah iklim global dibahas.

Both mean the same thing. The second version:

puts di perpustakaan at the beginning,
slightly emphasizes the location (“In the library…”).

Word order is quite flexible in Indonesian, especially for time and place phrases, which can be moved to the front for emphasis or style.

What would be a natural active-voice version of this sentence?

A common active version would be:

Di perpustakaan, mereka membahas masalah iklim global.
= In the library, they discuss the global climate issue.

Or without fronting the place phrase:

Mereka membahas masalah iklim global di perpustakaan.

Here:

mereka = they (the doer/subject)
membahas = discuss (active verb: meN-
- bahas)
masalah iklim global = the global climate issue (object)
di perpustakaan = in the library (place)

The original passive version Masalah iklim global dibahas di perpustakaan focuses more on the issue than on who is discussing it.