Kondisi jalan buruk.

In Indonesian, you usually do not need a present-tense verb like is/are between a subject and an adjective.

So:

Kondisi jalan buruk
literally looks like road condition bad,
but it naturally means The road condition is bad.

This is very normal in Indonesian.

Usually, no.

Kondisi jalan adalah buruk sounds unnatural to most speakers.
In Indonesian, adalah is usually used to link one noun phrase to another, especially in definitions or formal statements.

For example:

Indonesia adalah negara kepulauan.
= Indonesia is an archipelagic country.

But before an adjective like buruk, Indonesian normally just leaves the copula out:

Kondisi jalan buruk.

Kondisi means condition or state.
Jalan means road or street.

Together, kondisi jalan means:

• road condition
• the condition of the road
• the condition of the roads, depending on context

This noun + noun pattern is very common in Indonesian.

Here, buruk is the predicate of the whole sentence.

A good way to read it is:

[Kondisi jalan] [buruk].
= [The road condition] [is bad].

So this is not primarily saying bad road. It is saying that the condition is bad.

Compare:

• jalan buruk = a bad road / bad roads
• kondisi jalan buruk = the road condition is bad
• kondisi jalan yang buruk = the condition of a bad road or bad road conditions, depending on context

Here it means road.

Indonesian words can often belong to more than one word class depending on context.
Jalan can be:

• a noun: road / street
• a verb: to walk, to run, to function

In Kondisi jalan buruk, the context makes it clear that jalan is a noun.

Both are possible, but they feel slightly different.

Kondisi jalan buruk

• sounds concise
• can feel more general
• may sound a bit like a report, headline, or formal observation

Kondisi jalannya buruk

• sounds more tied to a specific road already known in context
• often feels a bit more natural in conversation

In speech, people might also simply say:

Jalannya buruk.
= The road is in bad condition / The road is bad.

In this kind of sentence, -nya often makes the noun sound more definite, more specific, or more topical.

So:

• jalan = road / roads
• jalannya = roughly the road, that road, or its road, depending on context

In Kondisi jalannya buruk, jalannya helps signal that you are talking about a particular road or the road already being discussed.

It is not exactly the same as English the, but it often overlaps with that idea.

Yes, that works too.

Keadaan and kondisi are similar:

• kondisi = condition, often a bit more formal or technical
• keadaan = state / condition / situation, often a bit broader or more everyday

So both are possible:

• Kondisi jalan buruk
• Keadaan jalan buruk

The first may sound slightly more formal or report-like.

Both can mean bad, but they are not identical.

Buruk

• more neutral
• often used for conditions, situations, systems, performance
• common in formal or written language

Jelek

• more colloquial
• often means ugly, poor-looking, or bad quality

For road conditions, buruk is often the better choice, especially in formal speech, news, or reports.

So:

• Kondisi jalan buruk = very natural
• Kondisi jalan jelek = understandable, but less formal and less standard in this kind of context

Indonesian often leaves that open unless the context makes it clear.

So Kondisi jalan buruk could mean:

• The road condition is bad
• Road conditions are bad
• The condition of the road is bad

Context tells you which one is meant.

If you want to be more specific, you can add words:

• Kondisi jalan ini buruk. = The condition of this road is bad.
• Kondisi jalan-jalan di kota ini buruk. = The condition of the roads in this city is bad.
• Kondisi banyak jalan buruk. = The condition of many roads is bad.

A simple English-friendly approximation is:

kon-DEE-see JAH-lan BOO-rook

A few notes:

• j in jalan sounds like English j in jam
• a is usually like the a in father
• u is like oo in food
• Indonesian stress is usually lighter and less dramatic than English stress

So try to keep it fairly even and smooth, rather than strongly stressing one syllable.

Yes, in some contexts it could.

Indonesian often allows short expressions like this to function either as:

• a full sentence: The road condition is bad
• a headline-style phrase: bad road conditions

In normal conversation or prose, people understand it as a sentence because Indonesian commonly omits is. In a headline, sign, or report title, it could also be read more like a label or phrase. Context decides.