Learn Hardcore Malay: Saya hanya buka dua tab pelayar ketika belajar di perpustakaan. - I only open two browser tabs when studying in the library.

buka is the base verb. In everyday, informal Malay, people very often use the base form instead of the meN- form, especially with common verbs like buka, makan, pergi, etc.
membuka is the meN--form (more “formal/complete” verb form). It sounds more formal or written, or slightly more careful speech.

In your sentence:

Saya hanya buka dua tab pelayar…
→ very natural in speech and casual writing.
Saya hanya membuka dua tab pelayar…
→ also correct, sounds a bit more formal/polished, common in essays, articles, or formal writing.

So yes, both are correct. The version with buka just sounds more conversational.

Where can I put hanya in the sentence? Can I move it or replace it?

Hanya means only / just. Its normal position is before the verb or before the phrase it limits:

Saya hanya buka dua tab pelayar…
→ “I only open two browser tabs…”

You could also say:

Saya buka hanya dua tab pelayar…
Focuses slightly more on the number dua (“only two tabs, not more”).

You can replace hanya with:

cuma (very common in speech, more casual):
Saya cuma buka dua tab pelayar…
sahaja (often comes at the end of a phrase, a bit more formal or neutral):
Saya buka dua tab pelayar sahaja ketika belajar di perpustakaan.

All of these are acceptable, with small differences in tone/formality and emphasis.

Why is it dua tab and not dua buah tab? Do I need a classifier like buah?

Malay often uses classifiers (like buah, orang, ekor) with numbers, but they are not always required, especially in casual speech.

dua tab = perfectly natural and common, especially for modern objects like tab.
dua buah tab = also correct; buah is a general classifier for inanimate objects. This sounds a bit more explicit or careful, more likely in formal descriptions or teaching materials.

For most everyday speech, especially with tech items, dua tab is fine and common.

Why isn’t tab pluralized (like tabs)? How is plural shown in Malay?

Malay does not mark plural with an -s like English. Plurality is usually shown by:

Context, or
A number, or
Reduplication (repeating the word).

In dua tab:

The number dua already shows it is plural (two).
So there’s no need for a plural form like tabs.

You might see reduplication for plural in other contexts:

buku-buku = books (general plural)
orang-orang = people

But with a clear number, reduplication is not used: you say dua buku, tiga orang, empat kereta, dua tab, not dua buku-buku.

What exactly does pelayar mean here? Doesn’t it usually mean sailor?

Yes, pelayar literally can mean sailor (someone who sails). But in modern IT vocabulary in Malay:

pelayar = (web) browser.

So:

tab pelayar ≈ “browser tab”.

You may also see or hear:

pelayar web = web browser
pelayar internet = internet browser
In practice, many people also just say browser (loanword from English).

In your sentence, tab pelayar is understood in a tech context as browser tab, not “sailor tab”.

Can I say tab pelayar web or is that redundant?

You can say tab pelayar web, and it will be understood, but often it’s more than you need:

tab pelayar in a tech context is usually enough to mean browser tab.
tab pelayar web or tab pelayar internet just adds extra clarity, especially in formal/technical texts or for learners.

In everyday conversation, tab pelayar or even just tab (if the context is clear) is common.

What’s the difference between ketika, semasa, apabila, and bila? Could I use them instead of ketika here?

All of these relate to when, but they differ in tone and usage:

ketika – fairly formal, common in writing, neutral in meaning.
semasa – also formal-ish, often in writing, similar to ketika.
apabila – “when / whenever”, common in more formal or careful speech and writing.
bila – informal, very common in everyday speech, often interchangeable with apabila in conversation.

In your sentence:

Saya hanya buka dua tab pelayar ketika belajar di perpustakaan.
Saya hanya buka dua tab pelayar semasa belajar di perpustakaan.
Saya hanya buka dua tab pelayar apabila belajar di perpustakaan.
Saya hanya buka dua tab pelayar bila belajar di perpustakaan. (very conversational)

All are understandable and basically mean the same thing. Ketika sounds neat and slightly more formal/neutral, which fits well in a textbook-style example.

Should it be ketika saya belajar instead of just ketika belajar? Where did the subject go?

Both are correct, but the subject “saya” is understood and can be omitted:

ketika saya belajar di perpustakaan
= “when I study/when I am studying at the library” (subject stated).
ketika belajar di perpustakaan
= literally “when studying at the library” (subject implied from context; here it’s saya).

In Malay, when the subject is the same as the main clause subject, it is often dropped in the subordinate clause if the meaning is clear. Your original sentence is natural and common.

Do I need sedang before belajar to mean “when I’m studying (right then)”?

You don’t have to use sedang here. The time clause introduces a general situation:

ketika belajar di perpustakaan
already means “when (I am) studying at the library”.

If you say:

ketika sedang belajar di perpustakaan

that puts a bit more emphasis on the ongoing nature of the action, similar to “when I am in the middle of studying at the library”. It’s still correct; it just adds a nuance of something in progress. For general habits, the version without sedang is very common and natural.

Is Saya the only option? What about Aku or dropping the pronoun?

You have a few options, with different levels of formality:

Saya – polite, neutral, safe in almost all situations (formal and informal).
Aku – more intimate or casual; common among close friends, siblings, or in certain dialects/social groups.
Dropping the pronoun – possible if the context is very clear, but usually for short or follow-up sentences.

Your sentence with different pronouns:

Saya hanya buka dua tab pelayar… – neutral, standard.
Aku hanya buka dua tab pelayar… – more casual/intimate.
(Without a clear context) just Hanya buka dua tab pelayar… would sound like a fragment; you’d normally keep the pronoun in a standalone sentence.

Could I say belajar di perpustakaan earlier, like Saya belajar di perpustakaan hanya buka dua tab pelayar?

No, that word order is not natural. The usual structure is:

Subject – Adverb (like hanya) – Verb – Object – Time/Place phrase

So:

Saya hanya buka dua tab pelayar ketika belajar di perpustakaan.

You can move the time/place phrase to the front for emphasis:

Ketika belajar di perpustakaan, saya hanya buka dua tab pelayar.
→ “When I study at the library, I only open two browser tabs.”

But you would not normally insert belajar di perpustakaan between the subject and the main verb buka like that. Keep belajar di perpustakaan either after the main clause or at the beginning as a separate time clause.

Is belajar di perpustakaan the same as di perpustakaan belajar?

Both are possible, but the usual and most natural order is:

belajar di perpustakaan (“study at the library”)

Di perpustakaan belajar is grammatically possible but tends to sound like:

A contrast or emphasis on the place: “At the library (I) study…”
Or like a sentence fragment: Di perpustakaan, (saya) belajar.

For your sentence, stick with:

ketika belajar di perpustakaan

That’s the smoothest and most common order.

How would I say the library (a specific library) instead of just perpustakaan?

Malay doesn’t use articles like the / a, so perpustakaan can mean a library or the library, depending on context.

If you want to make it clear that it’s a specific library, you can add extra information:

perpustakaan universiti – the university library
perpustakaan sekolah – the school library
perpustakaan itu – that library / the library (already mentioned)
perpustakaan kampus – the campus library

So for example:

Saya hanya buka dua tab pelayar ketika belajar di perpustakaan universiti.
→ “I only open two browser tabs when studying at the university library.”