Kontraktor terpaksa mengganti kusen yang rusak.

Mengganti is the verb with the meN- prefix, which commonly marks an active transitive verb in Indonesian.

• ganti = to change / change
• mengganti = to replace, to change something

Because the sentence has a direct object, kusen, Indonesian normally uses the active form:

• Kontraktor mengganti kusen = The contractor replaces the frame.

Using plain ganti here would sound less standard in careful Indonesian.

Terpaksa means forced to, had no choice but to, or was compelled to.

So:

• Kontraktor terpaksa mengganti kusen = The contractor had to replace the frame, usually because of some unwanted situation.

It often suggests necessity with a negative or reluctant feeling, not just neutral obligation.

Compare:

• harus = must / have to
• terpaksa = had to, unwillingly or because circumstances forced it

This follows normal Indonesian sentence order:

• Kontraktor = subject
• terpaksa mengganti = predicate
• kusen yang rusak = object

So the structure is basically:

Subject + predicate + object

Indonesian often uses a straightforward SVO order, much like English.

Kusen means a frame, especially a door frame or window frame.

So depending on context, it could refer to:

• a window frame
• a door frame
• a structural frame around an opening

In this sentence, the exact type may depend on the larger context.

Yang rusak is a relative clause describing kusen.

• yang = that / which / who
• rusak = damaged / broken

So:

• kusen yang rusak = the damaged frame / the frame that is damaged

A very common Indonesian pattern is:

noun + yang + description

Examples:

• mobil yang baru = the new car / the car that is new
• orang yang datang = the person who came

Because yang rusak comes right after kusen, so it naturally modifies kusen.

Indonesian usually places modifiers after the noun they describe:

• kusen yang rusak = the damaged frame

If you wanted to say the contractor was the one in bad condition, you would need a different structure, such as:

• Kontraktor yang rusak...
  though semantically that sounds odd, because rusak is more natural for objects than people.

Indonesian generally does not use articles like a, an, or the.

So:

• kontraktor can mean a contractor or the contractor
• kusen can mean a frame or the frame

Whether it is definite or indefinite is understood from context.

That is why kusen yang rusak can naturally be translated as:

• the damaged frame
• a damaged frame

depending on the situation.

No, Indonesian verbs do not change form for tense the way English verbs do.

So mengganti can mean:

• replace
• is replacing
• replaced
• will replace

The time is understood from context or from time words such as:

• kemarin = yesterday
• sekarang = now
• besok = tomorrow

Without extra context, the sentence is tense-neutral.

It can function a bit like both, depending on how you analyze it.

In this sentence, rusak is best understood as damaged/broken, describing the condition of the frame.

So:

• kusen yang rusak = the frame that is damaged / the broken frame

Many Indonesian words are flexible between adjective-like and verb-like uses, and rusak is one of them.

Yes. Indonesian nouns do not have to show singular/plural explicitly.

So kusen could mean:

• frame
• frames

In this sentence, English would often translate it as singular if the context suggests one specific damaged frame, but plural is also possible if the situation supports it.

If Indonesian wants to make plurality clearer, it can use:

• repetition: kusen-kusen
• a number: dua kusen
• a context word showing plurality

Yes. Indonesian often allows both active and passive versions.

Active:

• Kontraktor terpaksa mengganti kusen yang rusak.

Possible passive:

• Kusen yang rusak terpaksa diganti oleh kontraktor.

Here:

• mengganti = active
• diganti = passive

The active version focuses more on the contractor as the doer.
The passive version focuses more on the damaged frame.

The base word is ganti. When the meN- prefix is added, its form changes depending on the first sound of the root.

With ganti, it becomes:

• meN- + ganti → mengganti

This is a normal sound pattern in Indonesian morphology. Learners often just memorize the final active form as a vocabulary item, especially at first.

So it is useful to learn:

• ganti = change / replace
• mengganti sesuatu = replace something