Buku-buku di rak ditata dengan rapi oleh petugas perpustakaan.

In Indonesian, repeating a noun often marks plurality. So buku-buku means books rather than book.

A few useful notes:

• buku = book
• buku-buku = books

This kind of repetition is called reduplication. It is very common in Indonesian.

Also, plural marking in Indonesian is often optional if the context already makes it clear. So in some situations, buku by itself could still mean books. But buku-buku makes the plural meaning clearer and more explicit.

di rak is a prepositional phrase meaning on the shelf or at the shelf, depending on context. In natural English, on the shelf is usually the best translation here.

The important grammar point is this:

• di written separately = a preposition meaning in, on, at
• di- written attached to a verb = a passive prefix

So:

• di rak = on the shelf
• ditata = arranged / is arranged

A good learner tip: If di is followed by a place noun, it is usually written separately. If di- is part of a verb, it is written together.

They look similar, but they do different jobs.

• di rak: di is a preposition meaning location
• ditata: di- is a verb prefix that makes the verb passive

So the sentence contains:

• a location phrase: di rak
• a passive verb: ditata

This is very common in Indonesian, and learners often confuse the two because they are spelled almost the same.

ditata is the passive form of the verb based on tata, which has the idea of arranging, organizing, putting in order.

So ditata means:

• is arranged
• is organized
• is put in order

In this sentence, it means the books are being presented as the thing receiving the action.

Compare:

• Petugas perpustakaan menata buku-buku di rak.
  = The library staff arranges the books on the shelf.

• Buku-buku di rak ditata oleh petugas perpustakaan.
  = The books on the shelf are arranged by the library staff.

Indonesian uses the passive very naturally, often more naturally than English does.

This sentence is passive because the focus is on the books, not on the library staff.

Structure:

• Buku-buku di rak = the thing affected
• ditata = are arranged
• oleh petugas perpustakaan = by the library staff

A native English speaker may feel this sounds slightly formal because English often prefers the active voice. But in Indonesian, passive sentences like this are very normal.

dengan rapi means neatly or in a neat way.

Literally:

• dengan = with
• rapi = neat / tidy

But in Indonesian, dengan + adjective can function like an adverbial expression of manner. So:

• ditata dengan rapi = arranged neatly

This is a very common pattern:

• dengan cepat = quickly
• dengan baik = well
• dengan hati-hati = carefully

So although dengan often means with, here the whole phrase describes how the books are arranged.

oleh marks the agent in a passive sentence. In English, it usually corresponds to by.

So:

• oleh petugas perpustakaan = by the library staff / by the librarian / by the library attendant

It tells you who performs the action.

In passive Indonesian, oleh is often used when the agent needs to be stated clearly. If the agent is not important or already understood, it can sometimes be omitted.

Yes, often it can.

If you say:

• Buku-buku di rak ditata dengan rapi.

it still means that the books on the shelf are arranged neatly. The sentence simply does not say who arranged them.

This is very common in Indonesian. The passive is often used when:

• the doer is unknown
• the doer is obvious
• the doer is not important
• the speaker wants to focus on the result or the object

petugas perpustakaan literally means something like library staff member, library worker, library attendant, or sometimes librarian, depending on context.

Breaking it down:

• petugas = officer, staff member, worker, attendant
• perpustakaan = library

So petugas perpustakaan is a noun phrase meaning a person who works at the library.

It does not always mean a professional librarian in the strict sense. Sometimes library staff is the safest translation.

Indonesian does not use articles like English a, an, and the.

That means nouns such as buku-buku, rak, and petugas perpustakaan do not need articles.

The exact meaning depends on context. So this sentence could be understood as something like:

• The books on the shelf are neatly arranged by the library staff
• or, in another context, Books on the shelf are neatly arranged by library staff

Usually context tells you whether something is definite or indefinite.

The preposition di is broad. It can correspond to in, on, or at, depending on context.

So di rak literally just marks location at the shelf/rack. In natural English, the best translation here is usually:

• on the shelf

That is because books are typically placed on a shelf in English.

This is a good example of why you should not translate di mechanically as only in.

rak can mean shelf, rack, or shelving unit, depending on context.

In this sentence, shelf is probably the most natural translation because it is talking about books in a library.

So:

• di rak = on the shelf / on the shelves

Context decides the best English word.

Yes. The active version would be:

• Petugas perpustakaan menata buku-buku di rak dengan rapi.

That means the same basic thing, but the focus changes.

Compare:

• Passive: Buku-buku di rak ditata dengan rapi oleh petugas perpustakaan.
  Focus on the books.

• Active: Petugas perpustakaan menata buku-buku di rak dengan rapi.
  Focus on the library staff.

Both are grammatical and natural, but the passive is especially common in Indonesian when the speaker wants to foreground the object.

Yes, there is a difference.

• ditata usually suggests an action done by someone: arranged
• tertata often emphasizes the state or result: well-arranged / in an arranged state

So:

• Buku-buku di rak ditata dengan rapi oleh petugas perpustakaan.
  The books are arranged neatly by the library staff.
  This clearly includes an agent doing the action.

• Buku-buku di rak tertata rapi.
  The books on the shelf are neatly arranged / are in neat order.
  This focuses more on the condition of the books.

Both are useful, but ditata is the better choice when you want to mention who did it.

The structure is roughly:

• Buku-buku di rak = subject/topic
• ditata = passive verb
• dengan rapi = manner phrase
• oleh petugas perpustakaan = agent phrase

So the pattern is:

object/topic + passive verb + manner + agent

This is a very common Indonesian passive pattern.

In English, the equivalent order is similar:

The books on the shelf + are arranged + neatly + by the library staff.

No. Reduplication is one way to show plural, but it is not always required.

Indonesian often leaves nouns unmarked for number when the context is enough.

For example, depending on context, buku could mean:

• book
• books

But buku-buku makes the plural clearer.

In this sentence, using buku-buku helps make it obvious that more than one book is being talked about.