Learn Hardcore Malay: Setiap minggu, saya belajar di perpustakaan.

You can also say tiap-tiap minggu, which has the same meaning as setiap minggu, though setiap is more common in modern standard usage and sounds a bit cleaner and more formal.

Why is "di" used in "di perpustakaan"? What is the difference between "di" and "ke"?

In Malay:

di = “at / in / on” (location – where something happens)
ke = “to” (direction – movement towards somewhere)

In the sentence:

saya belajar di perpustakaan
→ “I study at the library” (location, so we use di)

If you wanted to talk about going to the library, you’d use ke:

Setiap minggu, saya pergi ke perpustakaan.
→ “Every week, I go to the library.”

So:

di perpustakaan = at/in the library
ke perpustakaan = to the library

Does "belajar" mean “to study” or “to learn”? How is it used in Malay?

Belajar covers both English ideas: “to study” and “to learn”, depending on context.

Examples:

Saya belajar di perpustakaan. – I study at the library.
Saya belajar bahasa Melayu. – I study/learn Malay.
Dia belajar bermain gitar. – He/She is learning to play the guitar.

Compare with:

mengajar = to teach
- Dia mengajar saya bahasa Melayu. – He/She teaches me Malay.

Belajar can be used:

without an object (focus on the activity)
- Saya suka belajar. – I like studying/learning.
with an object (what you study/learn)
- Saya belajar sains komputer. – I study computer science.

Why is there no word for “in/at the” before "library"? What does "perpustakaan" exactly mean?

Perpustakaan means “library” by itself. Malay does not use articles like “a / an / the”, so:

perpustakaan can mean “a library” or “the library” depending on context.

In di perpustakaan, you understand “in the library” or “at the library” from context, without needing to add anything.

If you really want to make it clearer that it’s one, non-specific library, you can say:

di sebuah perpustakaan – “in a library”

But in everyday sentences, di perpustakaan is perfectly normal and usually understood as “at the library / in the library”.

Is "saya" the only word for “I”? What about "aku"? Can I say "Setiap minggu, aku belajar di perpustakaan"?

Malay has several words for “I”, mainly:

saya – neutral, polite, standard; safe in most situations
aku – more informal/intimate; used with friends, family, or in casual speech

So yes, grammatically you can say:

Setiap minggu, aku belajar di perpustakaan.

However:

In formal contexts (talking to strangers, in class, in writing), saya is better.
Aku can sound too casual or even rude in the wrong context, especially with older people or people you don’t know well.

If you’re not sure which to use, stick with saya.

How do you pronounce "perpustakaan"? Where is the stress, and how many syllables does it have?

Perpustakaan is pronounced with 5 syllables:

per-pus-ta-ka-an

Approximate breakdown:

per – like “per” in “perfume” (short ‘e’)
pus – like “poos” but shorter (u as in “put” but a bit longer)
ta – “tah” (a as in “father”, but short)
ka – “kah”
an – like “un” in “under”, but nasal (n is clearly pronounced)

Stress in Malay is usually even or slightly on the second-last syllable:

per-pus-TA-ka-an (light stress on ta)

There are no silent letters; pronounce every syllable.

Is the comma after "Setiap minggu" necessary? Can I write the sentence without it?

The comma is optional, but common and stylistically good.

Setiap minggu, saya belajar di perpustakaan.
Setiap minggu saya belajar di perpustakaan.

Both are correct.

The comma just marks a brief pause after the time expression Setiap minggu, similar to English when you start a sentence with “Every week,”. In informal writing (texts, chats), people often skip it.

How does this sentence show that it’s a habit (something I do regularly) if there is no tense marker like “do / will / am”?

Malay typically does not use verb conjugations to mark tense or aspect. Instead, it relies heavily on:

time words – e.g. semalam (yesterday), esok (tomorrow), sekarang (now), setiap minggu (every week)
context

In:

Setiap minggu, saya belajar di perpustakaan.

The word setiap (“every”) signals a habitual action – something that happens regularly, like English “I study at the library every week.”
No extra marker is needed on the verb belajar.

Could I say "Pada setiap minggu" instead of "Setiap minggu"? Is "pada" necessary?

You can say:

Pada setiap minggu, saya belajar di perpustakaan.

But in everyday, natural Malay, it is more common to omit pada and just say:

Setiap minggu, saya belajar di perpustakaan.

Pada roughly corresponds to “on / at” in time expressions, e.g.:

pada hari Isnin – on Monday
pada pukul dua – at two o’clock

With setiap, it is usually dropped in modern standard usage unless you want to sound very formal or literary. So:

Prefer: Setiap minggu, saya belajar di perpustakaan.