Entah denah entah jadwal pengerjaan, salah satunya harus diubah.

It introduces two uncertain alternatives, similar to whether ... or ... or either ... or ... in English.

So Entah denah entah jadwal pengerjaan means something like:

Either the layout or the work schedule ... or Whether it’s the layout or the work schedule ...

The speaker is not specifying which one is the problem, only that one of the two is involved.

That repetition is the normal pattern. Indonesian often uses entah X entah Y to present two possibilities.

So:

• entah denah entah jadwal pengerjaan

means:

• either the layout or the work schedule

A single entah can also appear in other contexts with a meaning like who knows or I don’t know, but here the repeated form is a fixed structure for alternatives.

Denah usually means a layout, plan, diagram, or floor plan, depending on context.

It often refers to the arrangement of space or the planned structure of something. In this sentence, the best translation depends on the larger context, but layout or plan is likely the intended meaning.

This is a noun phrase:

• jadwal = schedule
• pengerjaan = the doing/execution/work process

So jadwal pengerjaan means something like:

• work schedule
• project schedule
• schedule for carrying out the work

Pengerjaan comes from kerja and refers to the process of doing or completing a task, often in a project or technical context.

Because Indonesian commonly links nouns directly without a separate word like of.

So:

• jadwal pengerjaan = schedule of work / work schedule
• jadwal rapat = meeting schedule
• rencana proyek = project plan

This is very normal in Indonesian. The first noun is usually the main noun, and the following noun modifies it.

No. This is a very common point of confusion.

Although salah often means wrong, the fixed expression salah satu means one of.

So:

• salah satu = one of
• salah satunya = one of them / one of those

In this sentence, -nya refers back to the two things already mentioned: denah and jadwal pengerjaan.

So salah satunya harus diubah means:

One of them has to be changed.

The -nya refers back to the previously mentioned options.

Here, the two options are:

• denah
• jadwal pengerjaan

So salah satunya literally means one of the two just mentioned.

This -nya often works like it, them, or the one in question, depending on context.

Because diubah is passive, and the sentence is talking about the thing that must be changed, not the person who changes it.

• mengubah = to change something
• diubah = to be changed

Compare:

• Kami harus mengubah denah. = We must change the layout.
• Denah harus diubah. = The layout must be changed.

In your sentence, the focus is on one of the two items, so the passive form harus diubah is the natural choice.

This is an important distinction:

• diubah = be changed by someone/something
• berubah = change, become different, undergo change on its own

Examples:

• Rencananya diubah. = The plan was changed.
• Rencananya berubah. = The plan changed.

So in your sentence, harus diubah suggests that someone needs to actively revise one of the two items.

That is normal in Indonesian. Passive sentences often leave the agent unstated if it is obvious, unknown, or unimportant.

So salah satunya harus diubah means:

One of them must be changed

without saying exactly by whom. The doer is understood from context.

English can do the same thing:

• It must be changed.

The comma separates the opening alternative phrase from the main clause:

• Entah denah entah jadwal pengerjaan,
• salah satunya harus diubah.

This makes the sentence easier to read and shows that the first part sets up the two possibilities, while the second part gives the main statement.

In practice, punctuation in Indonesian can vary a little, but this comma is natural and helpful here.

It sounds fairly neutral and natural, especially in written Indonesian or careful speech.

It is not extremely formal, but it is also not slangy. The vocabulary, especially denah, jadwal pengerjaan, and diubah, gives it a slightly professional or project-related tone.

In very casual speech, someone might choose simpler wording, but this sentence itself is perfectly normal.