النفايات البلاستيكية في كيس النفايات.

A fully vocalized reading is:

النفاياتُ البلاستيكيةُ في كيسِ النفاياتِ

A common transliteration is:

an-nifāyātu al-bilāstīkiyyatu fī kīsi an-nifāyāti

If you pause at the end, the case endings are often not pronounced clearly in normal speech, so you may hear something closer to:

an-nifāyāt al-bilāstīkiyya fī kīs an-nifāyāt

Because ن is a sun letter. When ال comes before a sun letter, the l sound assimilates to the next consonant.

So:

• النفايات is pronounced an-nifāyāt
• not al-nifāyāt

But in البلاستيكية, the first letter after ال is ب, which is a moon letter, so the l is pronounced normally:

• al-bilāstīkiyya

In Arabic, present-tense sentences often do not use a separate word for is/are.

So this is a normal nominal sentence:

• النفايات البلاستيكية = the plastic waste
• في كيس النفايات = in the garbage bag

Together, the meaning is understood as the plastic waste is in the garbage bag.

If you wanted a past-tense idea like was, you would normally use a verb such as كان.

This is a very common question.

In Modern Standard Arabic, non-human plurals usually take feminine singular agreement in adjectives and verbs.

So even though النفايات is plural, the adjective comes as:

• البلاستيكية = feminine singular

not a regular plural adjective.

This is normal Arabic grammar. Compare the same pattern in many other examples:

• الكتب الجديدة = the new books
• السيارات السريعة = the fast cars

Even though books and cars are plural, the adjective is feminine singular.

Because the adjective must match the noun in definiteness.

Here:

• النفايات is definite because it has الـ
• so the adjective must also be definite: البلاستيكية

That is why you get:

• النفايات البلاستيكية

If the phrase were indefinite, it would be:

• نفايات بلاستيكية = plastic waste

So the noun and adjective match in definiteness.

Because this is an iḍāfa construction, often called a genitive construction or possessive construction.

In كيس النفايات:

• كيس = bag
• النفايات = the waste / garbage

Together: bag of the waste, which in natural English is the garbage bag or the waste bag.

In an iḍāfa:

• the first noun usually does not take الـ
• the second noun determines whether the whole phrase is definite

So:

• كيس النفايات = the garbage bag
• كيس نفايات = a garbage bag / a bag of waste

The two instances do different jobs.

1. The first النفايات is the main noun of the sentence:

   • النفايات البلاستيكية = the plastic waste

2. The second النفايات is part of the phrase:

   • كيس النفايات = the garbage bag

So Arabic is not being redundant in a strange way here. The same noun simply appears in two different parts of the sentence.

Both are genitive here.

• في is a preposition, and prepositions make the following noun genitive:

  • في كيسِ

• In an iḍāfa, the second noun is also genitive:

  • كيسِ النفاياتِ

So with full case endings:

• في كيسِ النفاياتِ

In normal Arabic writing, these short vowels are usually not written, which is why learners often do not see them.

The structure is:

• النفايات البلاستيكية = the topic / subject
• في كيس النفايات = the predicate / comment

So this is a nominal sentence of the type:

• [noun phrase] + [prepositional phrase]

Very literally, it is something like:

• The plastic waste — in the garbage bag

In natural English, that becomes:

• The plastic waste is in the garbage bag

Yes, Arabic word order is somewhat flexible.

The given order is the most straightforward and neutral:

• النفايات البلاستيكية في كيس النفايات

You could also front the prepositional phrase for emphasis:

• في كيس النفايات النفايات البلاستيكية

That can sound more marked or literary, something like:

• In the garbage bag is the plastic waste

So the original order is the most natural basic choice for learners.

The singular is:

• نفاية = one piece/item of waste, waste material

The plural is:

• نفايات = waste, garbage, refuse

In English, waste is often treated like an uncountable noun, but Arabic can use a regular singular/plural pattern here.

Yes. البلاستيكية is the adjective plastic.

It comes from بلاستيك and is formed as a nisba adjective, a very common way to make adjectives in Arabic.

Base noun:

• بلاستيك = plastic

Adjective:

• بلاستيكي = plastic, made of plastic
• بلاستيكية = feminine singular form

Because it is describing النفايات, and Arabic uses feminine singular agreement with non-human plurals, the form here is:

• البلاستيكية

So grammatically it means the plastic in the plastic waste.