Learn Hardcore Indonesian: Gorden di ruang tamunya tebal, jadi sinar matahari hampir tidak masuk. - The curtain in his/her living room is thick, so sunlight almost doesn’t come in.

ruang tamu = living room (ruang = room, tamu = guest → “guest room” in the sense of living room)
-nya = his / her / their / its (possessive marker), also sometimes “the” in a specific sense

So ruang tamunya most naturally means “his/her living room” (or “their living room,” depending on context).

Key points about -nya:

It’s a neutral third-person possessive: does not show gender (no difference between his/her).
It can also mark definiteness (“the”), but in this sentence with gorden di ruang tamunya, the most natural meaning is “the curtains in his/her living room.”

Why is it ruang tamunya and not ruang tamu dia for “his/her living room”?

Both are possible, but they differ in style and frequency:

ruang tamunya
- Very common and natural.
- Compact: noun + -nya.
- Feels smooth and neutral in most contexts.
ruang tamu dia
- Grammatically OK, but feels a bit more spoken / informal or slightly clunky.
- Puts dia (he/she) after the noun, similar to “the living room of him/her.”

In most standard sentences like this, Indonesian uses noun + -nya rather than noun + dia:

bukunya (his/her book) is more natural than buku dia.

Why is there no word for “are” in Gorden di ruang tamunya tebal? Why not Gorden di ruang tamunya adalah tebal?

Indonesian usually does not use a verb like “to be” (am/is/are) before adjectives.

Structure:

Subject + adjective = “Subject is adjective”

So:

Gorden di ruang tamunya tebal
Literally: “The curtains in his/her living room thick” → “The curtains in his/her living room are thick.”

Using adalah:

Adalah is more often used before nouns, not adjectives:
- Dia adalah guru. = He/She is a teacher.
Dia tinggi. = He/She is tall. (no adalah, because tinggi is an adjective)

So you normally don’t say:

✗ Gorden di ruang tamunya adalah tebal (sounds unnatural).

What is the role of di in di ruang tamunya? Can I drop it?

Di is a preposition meaning “in/at/on” (for location).

gorden di ruang tamunya = the curtains in his/her living room

You cannot drop di here. If you said:

gorden ruang tamunya – this would be strange and unclear; it sounds like a compound noun (“living-room curtains”), but the structure is off.

You need di to clearly mark location:

buku di meja = the book on the table
orang di rumah itu = the person in that house

What does jadi mean in this sentence, and is it the same as “to become”?

Jadi has two main uses:

As a verb: “to become”
- Dia jadi marah. = He/She became angry.
As a conjunction: “so / therefore”
- Gorden di ruang tamunya tebal, jadi sinar matahari hampir tidak masuk.
  = “The curtains in his/her living room are thick, so sunlight hardly comes in.”

In this sentence, jadi is a conjunction connecting cause and effect:

cause: the curtains are thick
effect: sunlight hardly comes in

So here it does not mean “become”; it means “so / therefore.”

What is the nuance of hampir tidak in sinar matahari hampir tidak masuk?

Hampir tidak literally means “almost not”, and is usually translated as “hardly / barely / almost never / almost doesn’t.”

sinar matahari hampir tidak masuk = sunlight hardly comes in / sunlight almost doesn’t come in.

Structure:

hampir = almost
tidak = not
masuk = enter / come in

Compare:

sinar matahari tidak masuk = sunlight does not come in (strong, absolute)
sinar matahari hampir tidak masuk = sunlight hardly comes in (there is some, but very little)

Can hampir go after tidak, like tidak hampir masuk?

No, that would be very unusual and confusing.

Natural: hampir tidak [verb/adjective]
- Dia hampir tidak makan. = He/She hardly eats.
- Saya hampir tidak tidur tadi malam. = I hardly slept last night.

Tidak hampir masuk would be interpreted as something like “not almost enter,” which doesn’t convey the intended meaning of “hardly enters.”

So you should keep the pattern hampir tidak + verb/adjective.

What does masuk mean here, and why is there no ke (to)?

Masuk means “to enter / to come in.” It can be used:

Without an explicit destination, if the destination is obvious:
- Sinar matahari hampir tidak masuk.
  = Sunlight hardly comes in (into the room – understood from context).
- Silakan masuk. = Please come in.
With a preposition when you want to specify the destination:
- Sinar matahari hampir tidak masuk ke kamar itu.
  = Sunlight hardly enters that room.
- Dia masuk ke rumah. = He/She goes into the house.

In your sentence, the destination is clearly the living room, so it’s natural to just say masuk without ke.

Why use sinar matahari instead of just matahari or cahaya matahari?

The nuances:

sinar matahari
- sinar = ray / beam (of light)
- Literally: “sun rays” or “sunlight.”
- Very common and natural in this context (light entering a room).
matahari
- The sun (the star itself).
- Saying matahari hampir tidak masuk sounds odd, like “the sun itself hardly enters.”
cahaya matahari
- cahaya = light
- Means sunlight as well.
- Also correct and natural, but sinar matahari is very common and a bit more concrete (focusing on rays).

So sinar matahari hampir tidak masuk is a very natural way to say “sunlight hardly comes in.”

Can I change the word order to start with the sunlight part, like in English?

Yes, you can rephrase while keeping natural Indonesian word order. For example:

Sinar matahari hampir tidak masuk karena gorden di ruang tamunya tebal.
= Sunlight hardly comes in because the curtains in his/her living room are thick.

Here:

karena = because
The cause/effect order is reversed, but the sentence is still clear and natural.

You could also say:

Karena gorden di ruang tamunya tebal, sinar matahari hampir tidak masuk.
(Because the curtains… , sunlight hardly comes in.)

All of these are acceptable; you just change which part you want to emphasize.