Learn Hardcore Indonesian: Rumah tua itu kecil.

So Rumah tua itu kecil literally feels like: That old house small.
The idea “is” is understood from the word order: subject + adjective.

You can sometimes use adalah between the subject and a noun phrase (e.g. Dia adalah dokter = He is a doctor), but you don’t normally use adalah before a simple adjective like kecil.

What does itu mean here, and why is it after rumah tua instead of before?

Itu is a demonstrative. Its core meaning is that, but in many contexts it works like English the (showing a specific thing already known in the context).

In Indonesian, ini and itu usually come after the noun phrase:

rumah itu = that house / the house
buku ini = this book

In our sentence:

rumah tua = old house
rumah tua itu = that old house / the old house

So itu comes after the whole noun phrase rumah tua, not before it.

How can I tell which adjective belongs to the noun and which one is the main description of the sentence?

A useful rule of thumb:

Adjectives before ini/itu usually belong to the noun (they are part of the noun phrase).
Adjectives after ini/itu are usually the predicate (the main description of the sentence).

In Rumah tua itu kecil:

rumah tua (before itu) → tua belongs to the noun rumah ⇒ old house
kecil (after itu) → this is the main description ⇒ is small

Compare:

Rumah kecil itu tua.
- rumah kecil = small house (kecil belongs to rumah)
- tua = is old (main description)

So the position relative to itu (or ini) tells you what is modifying the noun and what is the predicate.

Can this sentence also mean The house is old and small?

Not exactly. The structure focuses on:

Subject: the old house
Predicate: is small

So the clearest reading is:

That old house is small.

Of course, if it is called rumah tua (old house), it is understood to be old, but the grammar only makes kecil the main statement.

If you want to say The house is old and small, you would normally say:

Rumah itu tua dan kecil.
(That house is old and small.)

Here both tua and kecil are predicate adjectives describing rumah itu.

Why do adjectives like tua and kecil come after the noun, not before like in English?

In Indonesian, adjectives that directly describe a noun normally come after the noun:

rumah besar = big house
mobil merah = red car
orang tinggi = tall person

So rumah tua is literally house old but means old house.

English: adjective + noun
Indonesian: noun + adjective

When an adjective is used as the predicate, it also comes after the subject:

Rumah itu kecil. = The house is small.
Mobil itu mahal. = The car is expensive.

Our sentence combines both patterns:

rumah tua (noun + adjective)
itu kecil (demonstrative + predicate adjective).

Does Rumah tua itu kecil talk about one house or several houses?

By default, Indonesian nouns do not show singular or plural. Rumah can mean house or houses depending on context.

In this sentence:

In most natural contexts, Rumah tua itu kecil will be understood as one specific old house:
- That old house is small.
- The old house is small.

To make it clearly plural, you can:

Reduplicate the noun: Rumah-rumah tua itu kecil-kecil.
= Those old houses are small (each one is small).

Or use a plural word like banyak:

Banyak rumah tua itu kecil.
= Many of those old houses are small.

Can I leave out itu and just say Rumah tua kecil?

In normal, full-sentence speech, Rumah tua kecil sounds incomplete or more like a noun phrase, not a full sentence. It could be interpreted as:

a small old house

rather than The old house is small.

To make it a clear, natural sentence, you usually keep itu (or ini) or some other determiner/context:

Rumah tua itu kecil. = That old house is small.
Rumah tua di kampung itu kecil. = The old house in that village is small.

You might see something like Rumah tua kecil in headlines, labels, or note-taking, where grammar is often shortened, but in regular speech you want itu (or similar) to mark the subject as a specific thing.

When should I translate itu as that and when as the?

Technically, itu means that, but in practice it can often be translated as the, because English forces you to choose.

Rough guideline:

If there is a clear contrast with something near the speaker or listener, itu feels more like that:
- Rumah tua itu kecil, tapi rumah baru ini besar.
  = That old house is small, but this new house is big.
If you’re just talking about something already known in the context, English might prefer the:
- Rumah tua itu dekat pasar.
  = The old house is near the market.

So Rumah tua itu kecil could be translated as either:

That old house is small. (more literal)
The old house is small. (very natural in many contexts)

What is the difference between tua and lama for old in a phrase like this?

Both can be translated as old, but they have different typical uses and nuances:

tua
- Core idea: old in age / physically old.
- Used for people and things.
- rumah tua → an old (aged) house, often with an old style or long existence.
lama
- Core idea: long time / former / not new.
- With rumah, it can mean the former/previous house, or one that has been owned/used for a long time.
- rumah lama might suggest the house you used to live in, or the previous property, more than emphasizing its age.

So:

Rumah tua itu kecil.
= That old (aged) house is small.
Rumah lama itu kecil.
= That former/old (previous) house is small.
(depending on context, it may be about previousness, not just age.)

If I want to say That old house is very small, where do I put very?

You have a few natural options. The simplest:

Rumah tua itu sangat kecil.
Rumah tua itu kecil sekali.

Both mean That old house is very small.

Explanation:

sangat goes before the adjective:
- sangat kecil = very small
sekali goes after the adjective:
- kecil sekali = very small

But the basic sentence structure stays the same:

Rumah tua itu (subject)
sangat kecil / kecil sekali (predicate)

Can I change the word order to Kecil rumah tua itu?

Not in normal, neutral Indonesian. Kecil rumah tua itu is either wrong or sounds very poetic/marked, and not something you should copy as a learner.

The usual neutral word order in a sentence like this is:

Subject + predicate adjective
Rumah tua itu kecil. = That old house is small.

Putting kecil first would only be used in special rhetorical or poetic contexts, similar to saying Small is that old house in English—unusual and stylistically marked.