الباب المقاوم للحريق مغلق تماما.

Because Arabic usually omits the present-tense to be in simple statements.

So:

• الباب المقاوم للحريق = the fire-resistant door
• مغلق تماما = completely closed

Together, they mean The fire-resistant door is completely closed.

This is called a nominal sentence in Arabic. If you wanted past or future, then Arabic would use a verb or a form of كان.

It is:

• الباب المقاوم للحريق = the subject
• مغلق تماما = the predicate

More specifically:

• الباب = the door
• المقاوم للحريق = resistant to fire / fire-resistant
• مغلق = closed
• تماما = completely, totally

So the structure is:

[subject] + [description of the subject]

Because المقاوم is an adjective describing الباب, and Arabic adjectives normally agree with the noun they describe in definiteness.

Since الباب means the door and is definite, the adjective must also be definite:

• الباب = the door
• المقاوم = the resistant

Together:

• الباب المقاوم = the resistant door

If the noun were indefinite, the adjective would also be indefinite:

• بابٌ مقاومٌ للحريق = a fire-resistant door

Arabic often expresses ideas like English compound adjectives in a more expanded way.

Here:

• المقاوم comes from the verb قاوم = to resist
• لـ = to / against
• الحريق = fire

So المقاوم للحريق literally means the one resistant to fire or resistant against fire.

This is a very natural Arabic way to say fire-resistant.

Grammatically, it is an active participle from قاوم. But in this sentence it functions like an adjective.

So although its form comes from a verb, in actual use it behaves like an adjective meaning:

• resisting
• resistant

This is very common in Arabic. Many descriptive words are participles used adjectivally.

Because the adjective المقاوم needs something to show what the door is resistant to.

That role is expressed with the preposition لـ here.

• لِ + الحريق becomes للحريق
• This means roughly to fire or against fire

So:

• مقاوم للحريق = resistant to fire

This contraction is normal:

• لِ + الـ → للـ

Because مغلق describes the door’s state: it is closed.

It is a passive participle from أغلق = to close.

So:

• مغلق = closed
• يُغلَق = is being closed / gets closed
• أُغلِقَ = was closed

In this sentence, the point is not the action of closing, but the condition of the door now. That is why مغلق is the natural choice.

Both can mean closed.

In Modern Standard Arabic:

• مغلق is often more formal and common in writing
• مقفول is also understood and widely used, especially in everyday speech varieties

So in a formal MSA sentence like this, مغلق sounds very natural.

تماما means completely, totally, or entirely.

It intensifies مغلق:

• مغلق = closed
• مغلق تماما = completely closed

It functions like an adverb in English, even though its Arabic grammar is a little different internally.

Because it modifies the word مغلق and Arabic commonly places this kind of intensifier after the word it describes.

So:

• مغلق تماما = completely closed

This is the most natural order here.

A fully vocalized version would be:

البابُ المقاومُ للحريقِ مُغلَقٌ تمامًا

A careful pronunciation would be approximately:

al-bābu al-muqāwimu lil-ḥarīqi mughlaqun tamāman

Notes:

• البابُ is nominative because it is the subject
• المقاومُ matches البابُ
• الحريقِ is genitive because it comes after لِ
• مُغلَقٌ is nominative because it is the predicate of a nominal sentence
• تمامًا ends with -an in formal full pronunciation

In normal reading and speech, these endings are often not fully pronounced.

Because it is an adjective describing الباب, and adjectives in Arabic agree with the noun they modify in:

• definiteness
• gender
• number
• case

Since الباب is nominative here, المقاوم is also nominative.

So in full vocalization:

• البابُ
• المقاومُ

They match.

Yes. It is one noun phrase:

• الباب = the door
• المقاوم للحريق = fire-resistant

Together they form:

the fire-resistant door

So the sentence does not mean:

• The door. The fire-resistant one is completely closed.

Instead, the whole phrase is the subject:

• The fire-resistant door = subject
• is completely closed = predicate

Yes. That means:

The door is completely closed.

The longer version simply adds more information:

• الباب مغلق تماما = The door is completely closed.
• الباب المقاوم للحريق مغلق تماما = The fire-resistant door is completely closed.

So المقاوم للحريق is just extra description of the door.

In English, modifiers often come before the noun:

• fire-resistant door

In Arabic, the noun usually comes first, and the describing words come after it:

• الباب المقاوم للحريق

So Arabic builds it more like:

• the door [that is] resistant to fire

This noun-first pattern is very common.

Yes, depending on context.

مغلق تماما can mean:

• completely closed
• completely shut
• fully closed

English choice depends on style and situation, but the Arabic is the same.

Yes, but it is straightforward here.

باب is grammatically masculine singular, so the adjectives/predicate are also masculine singular:

• المقاوم
• مغلق

If the noun were feminine, those forms would change accordingly.

Yes. It sounds natural in Modern Standard Arabic and would fit formal contexts such as:

• building instructions
• safety descriptions
• technical writing
• official notices

The phrase المقاوم للحريق especially has a formal, technical feel, which suits MSA well.