النجوم في السماء.

A careful MSA pronunciation is:

an-nujūmu fī as-samāʾi

A few important points:

• النجوم is written with الـ, but because ن is a sun letter, the l sound of الـ is not pronounced. So it sounds like an-nujūm, not al-nujūm.
• السماء works the same way: س is also a sun letter, so it sounds like as-samāʾ, not al-samāʾ.
• The ū in nujūm is a long vowel.
• The final ء in السماء is a hamza, a small glottal stop.

If you pause at the end of the sentence, you will often hear:

an-nujūm fī as-samāʾ

with the final case endings not pronounced.

Because Arabic often uses nominal sentences in the present tense without a verb meaning to be.

So instead of saying something like The stars are in the sky, Arabic simply says:

• النجوم = the stars
• في السماء = in the sky

Together, that naturally means The stars are in the sky.

This is very normal in Arabic. In the present tense, is / are / am is usually not stated.

It is most naturally understood as a full sentence in MSA:

The stars are in the sky.

Grammatically, it is a nominal sentence:

• النجوم = the topic / subject-like part
• في السماء = the predicate, telling where they are

Without context, someone could also see it as a short descriptive phrase, but in normal learning contexts it is usually treated as a complete sentence.

Because both nouns are definite:

• النجوم = the stars
• السماء = the sky

Arabic uses الـ to mark definiteness, similar to the in English.

So this sentence is not talking about just any stars or any sky in a vague way. It is speaking definitively: the stars and the sky.

في is a preposition meaning in.

So:

• في السماء = in the sky

This is one of the most common Arabic prepositions. Like English prepositions, it connects a noun to the rest of the sentence and gives information such as place, time, or position.

Because السماء comes after the preposition في, and nouns after prepositions are normally in the genitive case in MSA.

So in full case-marked Arabic:

• في السماءِ = fī as-samāʾi

That final -i is the genitive ending.

In everyday speech, in pause, or in less formal pronunciation, learners often hear it without the case ending clearly pronounced:

• في السماء = fī as-samāʾ

Both are connected to the same written form; the difference is mainly about full grammatical pronunciation.

In a fully vocalized MSA sentence, النجوم is nominative because it is the opening noun of the nominal sentence, the mubtadaʾ.

So it would be:

النُّجُومُ
an-nujūmu

The final -u is the nominative ending.

Again, in normal pause or less formal reading, that ending is often not heard clearly.

The singular is:

نجم = star

So:

• نجم = a star
• النجوم = the stars

نجوم is a broken plural, which means the plural is formed by changing the internal pattern of the word rather than just adding a regular ending.

This is very common in Arabic.

Because Arabic has two major ways to make plurals:

1. Sound plurals: formed by adding a regular ending
2. Broken plurals: formed by changing the word pattern itself

Here:

• singular: نجم
• plural: نجوم

The plural is not made by simply adding a suffix. The shape of the word changes internally, so it is called a broken plural.

English has something a little similar in irregular plurals like man → men, though Arabic uses this system much more often.

You can, but it changes the feel of the sentence.

The basic neutral order is:

النجوم في السماء = The stars are in the sky.

If you say:

في السماء النجوم

it sounds more marked or literary, with extra focus on in the sky. Arabic allows this kind of variation more than English does, but beginners should usually learn the neutral pattern first.

So for standard, straightforward usage, النجوم في السماء is the best choice.

That depends on the situation.

In fully correct formal MSA, you would say:

an-nujūmu fī as-samāʾi

But in many real-life situations, even educated speakers may soften or drop final case endings, especially when pausing. So you may hear something closer to:

an-nujūm fī as-samāʾ

For a learner:

• It is good to understand the case endings.
• It is also good to know that in actual speech, they are often reduced or omitted.

So yes, they matter in grammar and careful recitation, but you will not always hear them strongly in everyday formal speech.