در خانه باز است.

Here it is door.

A big reason this sentence can confuse learners is that در can mean both:

• door
• in / at / inside

In writing, both look exactly the same: در.

What tells you the meaning here is the structure of the whole sentence. This sentence is understood as درِ خانه باز است: the house’s door is open / the door of the house is open.

So the first word is the noun door, not the preposition in.

Persian usually does not use a separate word like English of in this kind of phrase. Instead, it uses the ezafe construction.

So the underlying form is:

• درِ خانه
• dar-e xâne
• literally: door-of house

That little -e sound links the two nouns. It is what gives the sense of of.

So:

• درِ خانه = the house door / the door of the house

Because Persian writing often leaves out short vowels.

The ezafe is usually pronounced, but in normal spelling it is often not written. So:

• written: در خانه
• read as: dar-e xâne

This is very common in Persian. Native readers usually understand it from context.

So although you see در خانه, the intended reading in this sentence is درِ خانه.

Because Persian basic sentence order is often different from English.

In English, you say:

• The door is open

In Persian, the descriptive part comes before the verb to be:

• باز است
• open is

So the full sentence is structured like:

• درِ خانه = the door of the house
• باز = open
• است = is

Literally: The house door open is.

That is normal Persian word order.

Yes, باز can mean different things depending on context.

Common meanings include:

• open
• again

In this sentence, it means open because it is acting as an adjective with است:

• باز است = is open

If باز meant again, the sentence would need a different structure and would not make sense in this context.

Persian does not have a word exactly like English the.

Definiteness is often understood from context. So:

• درِ خانه can mean a house door or the house door
• in real context, it is usually understood as the door of the house

This is very normal in Persian. Learners often want to see a separate word for the, but Persian usually does not need one.

A careful pronunciation is:

• dar-e xâne bâz ast

A few notes:

• درِ = dar-e
• خانه = xâne
• باز = bâz
• است = ast

In everyday spoken Persian, you will often hear a more colloquial version such as:

• dar-e xune bâze

So the written sentence is standard, but ordinary speech often sounds a bit different.

Yes. In conversation, a very natural spoken version is:

• درِ خونه بازه
• dar-e xune bâze

Differences from the more formal version:

• خانه becomes خونه in colloquial speech
• است becomes ـه / e in speech, so باز است becomes بازه

So:

• formal/written: درِ خانه باز است
• colloquial/spoken: درِ خونه بازه

Both mean the same thing.

In Persian, the main noun usually comes first, and the possessor or describing noun comes after it with ezafe.

So Persian says:

• door-of house

not:

• house door in the English order

This pattern is very common:

• کتابِ علی = Ali’s book
• درِ خانه = the door of the house
• اسمِ من = my name

So درِ خانه follows a normal Persian pattern: main noun + ezafe + second noun.

In formal written Persian, است is normally kept.

So the standard form is:

• درِ خانه باز است

In everyday speech, however, است is usually reduced rather than fully pronounced. That is why people often say:

• درِ خونه بازه

So in practice, spoken Persian often does not use the full است, but standard written Persian usually does.