Habuk di rak buku melekat pada jari saya ketika saya mengemas.

Habuk means dust, especially household dust (like on furniture, shelves, fans, etc.). It often suggests visible, sometimes slightly thicker dust.

Debu also means dust, but:

• It can be more general or finer dust (e.g. dust in the air, road dust, ash-like dust).
• In many contexts, habuk and debu can be swapped without changing the meaning much.

In your sentence, habuk di rak buku = “the dust on the bookshelf”.
Using debu di rak buku would still be understandable, but habuk feels more natural for that “dusty shelf” image in a house.

Both di and pada can translate to “on/at”, but they’re used differently.

• di is the normal preposition for physical location:

  • di rak buku – on/at the bookshelf
  • di meja – on/at the table
  • di rumah – at home

• pada is more:

  • abstract, or
  • used for time, targets, or attachment:
    • pada hari Isnin – on Monday
    • pada saya – to me / in my opinion
    • melekat pada jari saya – stuck to my fingers

So:

• di rak buku = at/on the rack (its location)
• pada jari saya = attached to my fingers

That’s why the sentence has both: di for where the dust is, pada for what it sticks to.

You can say di atas rak buku, and it’s not wrong. The nuance:

• di rak buku
  Very common, and usually already understood as “on the rack / on the shelf”, not inside it.

• di atas rak buku
  More explicitly “on top of the bookshelf”.
  This can sound a bit more specific, as if contrasting with “inside” or “under” the rack.

In everyday speech, di rak buku is normally enough and sounds more natural unless you really want to stress “on top” as opposed to some other part.

In the sentence:

Habuk di rak buku melekat pada jari saya...

melekat is an intransitive verb meaning “to stick / be stuck / cling”.

• Habuk … melekat = The dust stuck / is sticking

If you use melekatkan, it becomes transitive (you stick something to something):

• Saya melekatkan kertas pada dinding.
  I stick the paper to the wall.

So:

• habuk melekat pada jari saya = dust (itself) sticks to my fingers
• saya melekatkan habuk pada jari saya would mean I stick the dust onto my fingers (very uncommon and odd here).

Therefore, melekat is the correct form for “the dust stuck (by itself) to my fingers”.

Both are possible, but they carry a slightly different feel:

• melekat pada jari saya
  Emphasizes attachment/connection to the fingers (more “onto / to”).
• melekat di jari saya
  Emphasizes the location where the dust is (more “at / on”).

Because melekat already implies “to stick to something”, pada is very natural here and is often preferred when something adheres to a body part.

That said, melekat di jari saya would still be understood and not really “wrong” in casual conversation.

Malay usually does not mark plural with an -s like English. Context does the work.

• jari saya can mean:
  • my finger (singular) or
  • my fingers (plural).

If you really want to stress plurality, you can use:

• jari-jari saya – my fingers (clearly more than one)

But in natural speech and writing:

• jari saya is very commonly used and understood as “my fingers” if the context suggests more than one.

In your sentence, English would most naturally say “my fingers”, and jari saya comfortably covers that.

Both are possible:

• ketika saya mengemas – when I was tidying (up)
  Explicitly mentions saya (I).

• ketika mengemas – when (I was) tidying up
  The subject “I” is understood from context and omitted.

Malay often drops pronouns when it’s clear who is doing the action. In your full sentence, since you already said jari saya, it’s still clear “I” am the one cleaning, so:

Habuk di rak buku melekat pada jari saya ketika mengemas.

is also natural in conversation, slightly shorter and more casual.

mengemas most often means to tidy up / to put things in order.

Common uses:

• mengemas rumah – tidying/straightening up the house (putting things away, maybe some basic cleaning)
• mengemas bilik – tidying the room
• mengemas beg – packing a bag

It sits between “tidy up” and “pack”, depending on the object:

• With rumah/bilik (house/room) → “tidy up, straighten, put things in order”
• With beg/barang (bag/things) → “pack”

If you want to stress cleaning dirt (sweeping, mopping, removing stains), you might say:

• membersihkan rumah – cleaning the house
• mengelap habuk – wiping dust

In your sentence, ketika saya mengemas is well translated as “when I was tidying up”.

Malay verbs do not change form for tense. mengemas can mean:

• tidy / tidy up
• am tidying
• was tidying
• will tidy

The tense is taken from context or time words:

• tadi – earlier
• semalam – yesterday
• esok – tomorrow
• selalu – always, usually

If you want to make it clearly past, you can add a time word:

• Habuk di rak buku melekat pada jari saya tadi ketika saya mengemas.
  The dust on the bookshelf stuck to my fingers just now when I was tidying up.

Without a time word, the English translator must pick the most natural tense from context. “When I was tidying up” fits well as a typical story-like past event.

Yes, that is perfectly correct and quite natural:

Ketika saya mengemas, habuk di rak buku melekat pada jari saya.

Malay word order is flexible with adverbial clauses. You can place ketika… at the beginning or end:

• Habuk di rak buku melekat pada jari saya ketika saya mengemas.
• Ketika saya mengemas, habuk di rak buku melekat pada jari saya.

Both mean the same thing. The version starting with Ketika… slightly emphasizes the time/background first, like English “When I was tidying up, …”.

Yes, the core structure follows Subject – Verb – (prepositional phrase):

• Subject:
  Habuk di rak buku – The dust on the bookshelf

• Verb:
  melekat – stuck / sticks

• Prepositional phrase (where it stuck):
  pada jari saya – to my fingers

• Time clause:
  ketika saya mengemas – when I was tidying up

So, in rough order:

[Habuk di rak buku] [melekat] [pada jari saya] [ketika saya mengemas].
Subject – Verb – Location/Target phrase – Time clause

Yes, you can change saya to other pronouns, and it changes formality:

• saya – neutral, polite, standard; safe in almost all situations
• aku – informal, used with close friends, family, or people of equal/lower status

Examples:

• Habuk di rak buku melekat pada jari saya ketika saya mengemas.
  Neutral/polite.
• Habuk di rak buku melekat pada jari aku ketika aku mengemas.
  More casual/intimate, spoken with friends.

You should not mix them in one sentence (e.g. jari saya but ketika aku mengemas) unless you’re deliberately showing a change of perspective. In normal speech, keep the same person form throughout.