الهوا نظيف.

A common Levantine pronunciation is:

il-hawa nḍiif
or sometimes el-hawa nḍiif

A rough guide:

• الـ = il or el
• هوا = hawa
• نظيف = nḍiif

Notes:

• The ḍ sound in نظيف is a heavy/emphatic d sound.
• The ii in nḍiif is a long vowel, like the ee in see.

So the whole sentence sounds roughly like: il-HA-wa nḌEEF.

Because in Arabic, present-tense sentences like The air is clean usually do not use a separate word for is.

So:

• الهوا = the air
• نظيف = clean

Together:

• الهوا نظيف = The air is clean

This is very normal in both Levantine Arabic and Standard Arabic-type structures.

If you wanted a past or future meaning, then other words would appear:

• الهوا كان نظيف = The air was clean
• الهوا رح يكون نظيف = The air will be clean

Because here نظيف is a predicate adjective, not an adjective directly attached inside a noun phrase.

Compare these two ideas:

1. الهوا نظيف
   = The air is clean
   Here, نظيف is saying something about الهوا.

2. الهوا النظيف
   = the clean air
   Here, النظيف directly describes الهوا as part of one noun phrase.

This is a very important difference in Arabic.

So:

• الهوا نظيف = a full sentence
• الهوا النظيف = a phrase, not a complete statement by itself

Literally, الهوا means the air.

But depending on context, it can sometimes also suggest things like:

• the air outside
• the atmosphere
• the weather feel
• the breeze

So الهوا نظيف most directly means:

• The air is clean

But in some contexts, an English speaker might understand it more loosely as:

• The air is nice/fresh
• The atmosphere outside is clean

If someone specifically wants to talk about weather, another common word is الجو.

For example:

• الجو حلو = The weather is nice

الهوا is the normal colloquial Levantine form, while الهواء is the Standard Arabic form.

So:

• الهواء = more formal / Standard Arabic
• الهوا = everyday Levantine speech

Many colloquial words are spelled in a simpler way that matches how people actually say them.

So a learner should get used to seeing both:

• الهواء نظيف in formal Arabic
• الهوا نظيف in Levantine

نظيف means clean.

It is often used for physical cleanliness, such as:

• البيت نظيف = The house is clean
• المي نظيفة = The water is clean

With الهوا, it means the air is clean, fresh, or not polluted.

In everyday Arabic, نظيف can also sometimes have broader meanings like:

• tidy
• neat
• pure/clean in a general sense

But in this sentence, the most natural meaning is physical cleanliness of the air.

In this sentence, الهوا is treated as masculine, so the adjective appears as نظيف.

If the noun were feminine, the adjective would usually take ـة:

• masculine: نظيف
• feminine: نظيفة

For example:

• الهوا نظيف = The air is clean
• الغرفة نظيفة = The room is clean

This kind of agreement is very important in Arabic: adjectives usually match the noun in gender and number.

الـ is the Arabic definite article, meaning the.

So:

• هوا = air
• الهوا = the air

In Levantine pronunciation, الـ is often pronounced il- or el-, depending on the speaker and region.

So الهوا is pronounced roughly:

• il-hawa
• or el-hawa

No. In الهوا, the ل is pronounced normally.

That is because ه is not a sun letter.

So:

• الهوا = il-hawa, with the l clearly pronounced

Compare that with a word starting with a sun letter, where the l assimilates:

• الشمس = ish-shams / esh-shams

But here there is no assimilation:

• الهوا = il-hawa, not ih-hawa

Yes, it can. It is understandable and natural.

It would be especially natural in contexts like:

• talking about pollution
• describing fresh mountain air
• saying the air feels fresh after rain

For example:

• الهوا هون نظيف = The air here is clean
• بآخر الليل الهوا بصير أنظف = Late at night, the air gets cleaner

That said, depending on the exact situation, speakers might also use other expressions such as:

• الجو حلو = The weather is nice
• الهوا منعش = The air is refreshing
• الهوا نقي = The air is pure/clean

In Standard Arabic, the equivalent would usually be:

الهواء نظيف

The structure is the same:

• الهواء = the air
• نظيف = clean

So the main difference is mostly the noun form:

• Levantine: الهوا
• Standard Arabic: الهواء

You can, but the meaning changes.

• الهوا نظيف = The air is clean
• هوا نظيف = clean air or air is clean, depending on context, but it sounds less complete or less natural as a simple standalone sentence

If you want a clear full sentence meaning The air is clean, الهوا نظيف is the better choice.

Without الـ, it may sound more indefinite:

• في هوا نظيف هون = There is clean air here

So yes, the sentence with الـ is the most straightforward way to say The air is clean.