यह दरवाज़ा बड़ा है।

Because the normal Hindi word order is Subject + Description + Copula.

So:

• यह = this
• दरवाज़ा = door
• बड़ा = big
• है = is

Hindi usually puts the adjective before है, so यह दरवाज़ा बड़ा है is the natural way to say This door is big.

Here, यह means this.

It is a very common Hindi word that can work as:

• a demonstrative: this
• sometimes a pronoun: he / she / it / this one, depending on context

In this sentence, because it comes before दरवाज़ा, it clearly means this:
यह दरवाज़ा = this door

Because दरवाज़ा is a masculine singular noun, and the adjective बड़ा must agree with it.

Hindi adjectives like बड़ा change form depending on gender and number:

• बड़ा = masculine singular
• बड़ी = feminine singular
• बड़े = masculine plural or certain oblique uses

So:

• यह दरवाज़ा बड़ा है = This door is big.
• यह खिड़की बड़ी है = This window is big.

Since दरवाज़ा is masculine, बड़ा is correct.

You usually learn the gender of each noun as part of the word.

A helpful clue is that many Hindi nouns ending in -ा are masculine, and दरवाज़ा follows that pattern. But this is not a perfect rule for every noun in Hindi, so it is still best to memorize gender with the noun.

A good habit is to learn nouns in small phrases, for example:

• बड़ा दरवाज़ा = big door
• नई किताब = new book

That helps you remember both meaning and gender.

है means is.

It is the singular present-tense form of the verb to be in this kind of sentence.

So:

• यह दरवाज़ा बड़ा है = This door is big.

Without है, the sentence would sound incomplete in normal standard Hindi.

Compare:

• मैं खुश हूँ = I am happy.
• वह लंबा है = He is tall.
• वे बड़े हैं = They are big.

Use हैं for plural subjects and also for respectful singular subjects.

Examples:

• ये दरवाज़े बड़े हैं। = These doors are big.
• वे बड़े हैं। = They are big.
• आप ठीक हैं। = You are fine.
  (आप is grammatically treated with plural agreement as a mark of respect.)

In your sentence, दरवाज़ा is singular, so है is correct.

In careful, standard pronunciation, यह is often pronounced something like yah.

But in everyday speech, many speakers say something closer to yeh. That is very common.

So you may hear:

• यह दरवाज़ा बड़ा है pronounced roughly as
• yeh darvaaza baṛaa hai

Both the spelling यह and the common spoken pronunciation are normal to know.

बड़ा is pronounced roughly baṛā.

The ड़ sound is not the same as English d. It is a kind of flapped/r-like d sound, common in Hindi. Many learners hear it as something between d and r.

A rough guide:

• ब = ba
• ड़ = ṛ / flap sound
• ा = long aa

So बड़ा sounds roughly like buh-RAA with a quick flap in the middle.

It does not need to be perfect at first; the important thing is to notice that ड़ is different from plain द or ड.

Very broadly:

• यह = this
• वह = that

So:

• यह दरवाज़ा बड़ा है। = This door is big.
• वह दरवाज़ा बड़ा है। = That door is big.

In context, these can also mean he/she/it, but when placed before a noun like दरवाज़ा, they usually mean this/that.

Yes, but it means something slightly different.

• यह दरवाज़ा बड़ा है। = This door is big.
  You are describing the door.

• यह बड़ा दरवाज़ा है। = This is a big door.
  You are identifying this as a big door.

So the word order changes the emphasis and structure.

The plural would be:

ये दरवाज़े बड़े हैं। = These doors are big.

Notice all the changes:

• यह → ये = this/these in common usage
• दरवाज़ा → दरवाज़े = door/doors
• बड़ा → बड़े = big, agreeing with masculine plural
• है → हैं = is/are

This is a good example of agreement in Hindi.

Usually, an adjective like बड़ा comes before the noun when it directly describes it:

• बड़ा दरवाज़ा = big door

But in your sentence, बड़ा is part of the predicate:

• यह दरवाज़ा बड़ा है = This door is big

So it comes after the noun because the sentence is structured as This door + big + is.

Both patterns are normal:

• बड़ा दरवाज़ा = a big door
• दरवाज़ा बड़ा है = the door is big

Yes. One thing learners often notice is ज़.

That letter is ज with a dot underneath, called a nukta. It represents a z sound, so:

• दरवाज़ा is pronounced roughly darvaazaa

Many Hindi words of Persian or Arabic origin use letters with a nukta, and दरवाज़ा is one of them.

You may also sometimes see pronunciation or spelling variations in informal contexts, but दरवाज़ा is the standard form.

Yes. Hindi does not have articles exactly like English a/an/the.

So दरवाज़ा can mean:

• door
• a door
• the door

The context tells you which one is meant.

In यह दरवाज़ा बड़ा है, the presence of यह makes it specific, so it is clearly this door.