القميص أبيض.

In Arabic, the present tense of to be is usually not stated in simple sentences like this.

So Arabic says:

• القميص أبيض
• literally: the shirt white
• naturally: The shirt is white

This is called a nominal sentence in Arabic.

If you want was or will be, Arabic does use a verb, for example:

• كان القميص أبيض = The shirt was white
• سيكون القميص أبيض = The shirt will be white

Because القميص is the subject: the shirt, while أبيض is the predicate: white.

In Arabic, when an adjective is used as the predicate in a sentence like this, it is usually indefinite, even though in English we just say white without thinking about definiteness.

So:

• القميص أبيض = The shirt is white

But if both words are definite:

• القميص الأبيض

that usually means:

• the white shirt

So the second version is a noun phrase, not a full sentence.

It is an adjective in function, but more specifically in Arabic grammar it is the predicate (خبر) of the sentence.

So the structure is:

• القميص = the subject/topic (مبتدأ)
• أبيض = the predicate/comment (خبر)

Together they make a complete sentence: The shirt is white.

Arabic normally places adjectives after the nouns they relate to.

So in a phrase like:

• القميص الأبيض = the white shirt

the adjective comes after القميص.

In your sentence:

• القميص أبيض

the word أبيض also comes after the noun, but here it is not just modifying the noun inside a phrase. It is serving as the predicate of the whole sentence.

So although the order looks similar, the meaning is different:

• القميص الأبيض = the white shirt
• القميص أبيض = The shirt is white

Because قميص is a masculine singular noun, and the adjective must match it in gender and number.

So:

• قميص = masculine singular
• أبيض = masculine singular

If the noun were feminine, you would use the feminine form:

• السترة بيضاء = The jacket is white

So the adjective changes to match the noun.

الـ is the Arabic definite article, meaning the.

So:

• قميص = a shirt or shirt
• القميص = the shirt

In this word, الـ is pronounced clearly as al- because the next letter, ق, is a moon letter, not a sun letter.

So the beginning is pronounced roughly:

• al-qamīṣ

not assimilated.

A common pronunciation is:

• al-qamīṣ abyaḍ

If you include full case endings in careful Modern Standard Arabic, it is:

• al-qamīṣu abyaḍu

A rough guide:

• القميص = al-qamīṣ
• أبيض = abyaḍ

A few pronunciation notes:

• ق is a deep q sound, not an English k
• ص is an emphatic s
• ض is an emphatic d-type sound
• أ at the start of أبيض is a real glottal stop: a-byaḍ

In fully vocalized formal Arabic, yes.

The sentence would be:

• القميصُ أبيضُ

Both words are in the nominative, because:

• القميصُ is the subject
• أبيضُ is the predicate

However, in normal Arabic writing, these short vowel endings are usually not written, so you commonly see:

• القميص أبيض

This is a slightly more advanced point.

You might expect an indefinite predicate to look like أبيضٌ, but أبيض belongs to a special pattern, أفعل, often used for colors and certain adjectives. Words of this type are usually diptotes (ممنوعة من الصرف), which means they do not take tanwīn.

So in careful vocalization, the nominative form is:

• أبيضُ

not:

• أبيضٌ

This is normal and correct.

The difference is very important:

• القميص أبيض = The shirt is white
• القميص الأبيض = the white shirt

Why?

Because in القميص الأبيض, the adjective الأبيض is definite and directly modifies the noun. That makes the whole thing a noun phrase.

In القميص أبيض, the second word is indefinite and functions as the predicate, so it becomes a full sentence.

In normal, neutral Modern Standard Arabic, the usual order is:

• القميص أبيض

Starting with أبيض would sound marked, poetic, or dependent on context. It is not the basic form learners should use first.

So for standard, everyday sentence-building in MSA, stick with:

• subject + predicate
• القميص أبيض