الطيران مهم.

Because Arabic usually does not use a present-tense verb to be in simple sentences like this.

So:

• الطيران = the subject
• مهم = the description/predicate

Literally, Arabic says something like:

• Aviation important
• or Flying important

But the natural English translation is Aviation is important or Flying is important.

If you wanted past or future, Arabic would use extra words or verbs, but in the present tense it normally leaves is/am/are unstated.

This is a nominal sentence in Arabic, called جملة اسمية.

A nominal sentence often starts with a noun and has two main parts:

• المبتدأ — the topic/subject
• الخبر — what is said about it

Here:

• الطيران is the مبتدأ
• مهم is the خبر

So the structure is:

• [topic] + [comment about it]

That is a very common Arabic sentence pattern.

الـ is the Arabic definite article, usually equivalent to the.

So طيران can mean something like:

• flying
• aviation

And الطيران means:

• the flying
• aviation as a general concept
• sometimes air travel or aviation depending on context

In Arabic, abstract ideas are often expressed with the definite article where English may or may not use the.

So الطيران مهم is perfectly natural Arabic.

Yes. The ل of الـ is assimilated here because ط is a sun letter.

So although it is written:

• الطيران

it is pronounced more like:

• aṭ-ṭayarān

not:

• al-ṭayarān

In fully vowelled form, you may see:

• الطَّيَران

with a shadda on ط, showing the doubled sound.

Also, ط is an emphatic consonant, heavier than plain ت.

Because الطيران is grammatically masculine singular, so the adjective/predicate agrees with it.

That is why Arabic uses:

• مهم = important (masculine singular)

not:

• مهمة = important (feminine singular)

Even though aviation or flying is not a person, Arabic nouns still have grammatical gender, and adjectives must agree with that gender.

In a simple sentence like this, the predicate after a definite subject is usually indefinite.

So:

• الطيران مهم = Aviation is important

This is the normal pattern:

• definite subject + indefinite predicate

If you said الطيران المهم, that would usually mean:

• the important aviation
• or it would sound like a noun phrase, not a complete sentence

So مهم is indefinite because it is describing the subject in a sentence, not forming the important aviation as one combined phrase.

In fully formal Arabic with full vocalization, yes.

The fully inflected form would be:

• الطَّيَرانُ مُهِمٌّ

with:

• ـُ on الطيران because it is the subject
• ـٌ on مهم because it is the predicate and indefinite

But in normal modern writing, short vowels and case endings are usually omitted, so you normally just see:

• الطيران مهم

That is completely standard.

It can cover several related ideas, depending on context.

Common possibilities include:

• flying
• aviation
• air travel
• the field of aviation

In this short sentence, the broadest and safest understanding is something like:

• Aviation is important
• or Flying is important

This word comes from the root ط ي ر, which is connected with flying and birds.

No. Here it is a noun, not a verb.

It is a verbal noun or abstract noun, often called a masdar in Arabic grammar.

So although it is related to the idea to fly, in this sentence it functions as a noun meaning something like:

• flying
• aviation

That is why it can be the subject of the sentence.

Normally, for a simple neutral sentence, الطيران مهم is the best and most natural order.

Putting مهم first can happen in some contexts for style, focus, or poetic effect, but it is not the basic beginner pattern.

So if you just want to say Aviation is important, use:

• الطيران مهم

Yes. الطيران comes from the root ط ي ر, which is associated with flying and birds.

Some related words are:

• طار = he flew
• يطير = he flies / he is flying
• طائر = bird / flying thing
• طائرة = airplane
• طيران = flying / aviation

Learning the root helps you connect vocabulary and recognize word families more easily.

A fully vowelled version would normally be:

• الطَّيَرانُ مُهِمٌّ

You can break that down as:

• الطَّيَرانُ = aṭ-ṭayarānu
• مُهِمٌّ = muhimmun

In everyday reading and writing, though, you will almost always see the unvowelled form:

• الطيران مهم