Learn Hardcore Indonesian: AC di perpustakaan menyala secara otomatis ketika ruangan terlalu panas. - The AC in the library turns on automatically when the room is too hot.

AC is a direct borrowing from English, short for air conditioner. In Indonesian conversations and writing, people often use AC rather than spelling out penyejuk udara.

How do you pronounce AC in Indonesian?

You pronounce AC as two separate letters: “ah-chay” ([a.tʃe]). Each letter is read individually, not as a single syllable.

Why is it di perpustakaan and not ke perpustakaan?

In Indonesian, di marks location (“in/at”), whereas ke marks direction toward something (“to”). Since the sentence describes where the AC is (at the library), you use di perpustakaan.

What does perpustakaan mean, and how is it formed?

Perpustakaan means “library.” It’s formed from the root pustaka (meaning “book” or “collection of books”) plus the affixes per- and -an, which turn it into a noun indicating a place related to books.

What is the function of menyala here? Doesn’t it mean “to light up”?

Menyala is an intransitive verb meaning “to turn on” or “to be turned on,” as in a light or electrical device starting to operate. It’s built from the root nyala (meaning “a flame” or “light”) plus the active prefix meN-, so the device itself is doing the action of switching on.

Why not use menyalakan instead of menyala?

Menyalakan is a transitive verb meaning “to turn something on” (you, the agent, activate it). Menyala is intransitive: it describes the AC switching on by itself, fitting the idea of “turns on automatically.”

What does secara otomatis mean, and how does secara work?

Secara otomatis means “automatically.” Secara is a prefix used to turn an adjective into an adverbial phrase. So otomatis (automatic) becomes secara otomatis (“in an automatic manner”).

Why use ketika instead of saat or waktu?

All three words can introduce time clauses, but there are subtle differences:

ketika is more formal/literary and often used in writing.
saat is fairly neutral and common in both speech and writing.
waktu
- clause is slightly more colloquial.
  Here, ketika fits well in a written or formal context: “when the room gets too hot.”

What does terlalu panas mean? How is terlalu different from sangat?

Terlalu panas means “too hot.” Terlalu indicates an excess—beyond what’s comfortable. Sangat panas simply means “very hot” without implying that it’s more than acceptable. So terlalu panas explains why the AC kicks in.

Why use ruangan instead of kamar or bilik?

Ruangan is a general word for “room” or “space” and is often used in public or shared contexts (like libraries, offices, halls). Kamar usually refers to a bedroom or private room, and bilik is more formal/archaic for “small enclosed space.” In a library context, ruangan is the most natural choice.

The English version has “the” before “library” and “room.” Why doesn’t Indonesian use articles here?

Indonesian doesn’t have definite or indefinite articles like “the” or “a.” Instead, context tells you if you’re talking about a specific library or any library in general. Here, it’s understood you mean “the AC in the library” without needing an article.