Arabic nouns and adjectives are inflected for three numbers:

• Singular / المُفْرَِد
• Dual / المُثَنّى
• Plural / الجَمْع

Dual and plural in Arabic have different specificities which we’ll learn here.

Dual / المُثَنّى

When referring to two items or individuals, the dual is used – between the singular (for one thing/person) and plural (three or more things/people). To form a dual noun in Arabic, simply replace the singular ending with one of these suffixes: 

• In the nominative case (مَرْفُوع)

🢡 ـانِ… /āni/

• In the accusative (مَنْصوب) and genitive cases (مَجْرور)

🢡 ـَيْنِ… /ayni/ 

Dual nominative (المُثَنّى المَرْفُوع)	Dual accusative/genitive (المُثَنّى المَنْصُوب/المَجْرور)	Singular (المُفْرَد)
كِتابانِ  two books	كِتابَيْنِ two books	كِتاب  a book
وَلَدانِ  two boys	وَلَدَيْنِ  two boys	وَلَد  a boy

Note: The final tā marbūṭa (ة …ـة…) in singular nouns, is replaced by a regular ـتـ /t/ in dual endings:

Dual nominative (المُثَنّى المَرْفُوع)	Dual accusative / genitive (المُثَنّى المَنْصُوب / المَجْرور)	Singular (المُفْرَد)
مَدْرَسَتانِ  two schools	مَدْرَسَتَيْنِ  two schools	مَدْرَسَةٌ  a school

Noun modifications

In some cases, when the root of a word is weak or finishes with ي, و or hamza, its ending transforms before adding the dual suffix.

– Words ending with اء: 

• 🢡 If the ending اء is the mark of the feminine, the hamza turns into و :  

Dual (المُثَنّى)	Singular (المُفْرَد)
صَحْراوانِ two deserts	صَحْراء a desert
رِجْلانِ حَمْراوانِ two red legs	رِجْل حَمْراء a red leg

• 🢡 If the ending in اء is the mark of a weak root, the hamza is maintained or sometimes turns into و: 

Dual (المُثَنّى)	Singular (المُفْرَد)
كِساءان  two pieces of clothes	كِساء  a piece of clothing
لِقاءان (not لِقاوانِ) two meetings	لِقاء a meeting

– If a singular noun ends with a ى, it will become a ي:

Dual (المُثَنّى)	Singular (المُفْرَد)
مُسْتَشْفَيانِ  two hospitals	مُسْتَشْفى   a hospital
صَدَيانِ  two echoes	صَدى  an echo

Plural / الجَمْع

There are two types of plural in Arabic: 

• The sound plural (الجَمْعُ السالِمُ) which can be compared to the English regular plural.

• The broken plural (جَمْعُ التَكْسِيرِ) which can be compared to the English irregular plural.

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The sound masculine plural / جَمْعُ المُذَكّرِ السالِم

To form the sound masculine plural (جَمْعُ المُذَكَّرِ السالِم), we need to replace case endings in the singular form with these two suffixes:

• In the nominative case (مَرْفُوع)

🢡 ـونَ… /ūna/

• In the accusative (مَنْصوب) and genitive (مَجْرور) cases

🢡 ـِينَ… /īna/ 

Plural nominative (الجَمْع المَرْفُوع)	Plural accusative and genitive (الجَمْع المَنْصُوب والمَجْرور)	Singular (المُفْرَد)
مُهَنْدِسُونَ  engineers	مُهَنْدِسِينَ  engineers	🢠 مُهَنْدِس   engineer

Noun modifications

• For words ending with اء the hamza stays 

Plural (الجَمْع)	Singular (مُفْرَدال)
بَنّاؤُونَ masons	🢠 بَنّاءٌ mason	Nominative case (مَرْفُوع)
بَنّائِينَ  masons	🢠 بَنّاءً / بَنّاءٍ mason	Accusative and genitive cases (مَنْصُوب ومَجْرور)

• For words ending with ى, the alif disappears but the fatḥa that precedes stays

Plural (الجَمْع)	Singular (مُفْرَدال)
مُغَطَّونَ covered	🢠 مُغَطًّى (المُغَطَّى) covered	Nominative case (مَرْفُوع)
مُغَطَّينَ covered	🢠 مُغَطًّى (المُغَطَّى) covered	Accusative and genitive cases (مَنْصُوب ومَجْرور)

• For active participles of weak verbs, the final kasra and the ي belonging to the root disappear:

Plural (الجَمْع)	Singular (مُفْرَدال)
راضُونَ satisfied	🢠 راضٍ (الراضِي)  satisfied	Nominative case (مَرْفُوع)
راضِينَ satisfied	🢠 راضٍ (الراضِي) satisfied	Accusative and genitive cases (مَنْصُوب ومَجْرور)

The sound feminine plural / جَمْعُ المُؤَنّثِ السالِم

To form the sound feminine plural (جَمْعُ المُؤَنَّثِ السالِم), we need to replace case endings in the singular form with these two suffixes (we remove the ة if the word ends like this). 

• In the nominative case (مَرْفُوع)

 🢡 ـاتٌ… /ātun/

• In the accusative (مَنْصوب) and genitive cases (مَجْرور)

🢡 ـاتٍ… /ātin/ 

When the noun is indefinite, the final tanwīn appears.

Plural	Singular
مَلِكاتٌ (المَلِكاتُ)  queens	🢠 مَلِكةٌ (المَلِكةُ)  queen	Nominative case (مَرْفُوع)
سِجِلاتٌ (السِجِلاتُ)   registers	🢠 سِجِلٌّ (السِجِلُّ) register
مَلِكاتٍ (المَلِكاتِ)   queens	🢠 مَلِكةً (المَلِكةَ )/ مَلِكةٍ (المَلِكةِ) queen	Accusative and genitive cases (مَنْصُوب ومَجْرُور)
سِجِلاتٍ (السِجِلاتِ)  registers	🢠 سِجِلاً (السِجِلَّ) / سِجِلٍّ (السِجِلِّ) register

Noun modifications

• For nouns ending with ى, اة or اء this ending is replaced by a و or a ي (depending on the root letters):

With اة:

Plural (الجَمْع)	Singular (المُفْرَد)
قَنَوات canals/channels	🢠 قَناة canal/channel
حَيَوات lives	🢠 حَياة  life

With ى:

Plural (الجَمْع)	Singular (المُفْرَد)
عُظْمَيات  greatest (feminine)	🢠عُظْمى greatest (feminine)
حُبْلَيات pregnant	🢠 حُبْلى pregnant

With اء:

Plural (الجَمْع)	Singular (المُفْرَد)
سَمَاوات skies	🢠 سَماء sky
صَحْرَاوات deserts	🢠صَحْراء  desert

• For nouns whose singular pattern is فَعْل or فَعْلة and have a 2nd letter that’s neither a ي nor و, the sukūn generally turns into a vowel in the event of a sound plural (the same consonant as the 1st letter being fatḥa):

Plural (الجَمْع)	Singular (المُفْرَد)
سَجَدات  prostrations	🢠 سَجْدة prostration
جَلَسات  sessions	🢠 جَلْسة  session
ظُلُمات  obscurities	🢠 ظُلْمة obscurity

• Exceptions:

Plural (الجَمْع)	Singular (المُفْرَد)
سَنَوات  years	🢠 سَنة year
شَفَوات  lips	🢠 شَفة  lip
بَنات  daughters	🢠بِنْت daughter
أُمَّهات  mothers	🢠 أُمّ mother
أَخَوات sisters	🢠 أُخْت sister

Note: The sound feminine plural ending typically only applies to human entities.

Broken plurals / جَمْعُ التَكْسِير 

The Arabic language comprises a wide array of nouns and adjectives with an irregular plural form referred to as broken plural, or جَمْعُ التَكْسِير. This is analogous to the English equivalent like ‘man – men’, ‘goose – geese’, and ‘tooth– teeth’ or even ‘child-children’.

There are many broken plural patterns. Arabic grammarians have formulated distinctions between small numbers and collective plurals which are neglected today except for certain words such as:

أَحْرُف (less than 10 letters) / حُرُوف (beyond 10 letters) 🢠 (letter) حَرْف

أَشْهُر (less than 12 month) / شُهُور (beyond 12 month) 🢠 (month) شَهْر

Singular words are transformed into broken plural forms through different increments and internal changes. Taking the time to learn these patterns makes it easier to spot plurals within texts, as well as source their singular roots. Unfortunately, there are not any concrete regulations when creating broken plurals from singular words; some may have one or more versions while others could contain both broken and sound varieties. On top of that, it’s essential to note that these irregular formations are used more often than the sound “regular” plural constructions.

Most internal plurals follow the basic three-case declension. A significant number (notably among those of four syllables) are diptotic, some follow the diptotic-defective declination, finally others, few in number, are indeclinable (final in ى)

Triliteral root / الثُلاثي

Examples (أَمْثِلة)		Plural pattern (الوَزْن)
قِطّ  🢠 قِطَط  cats 🢠 cat	فِرْقَة 🢠 فِرَق  teams 🢠 team	فِعَل
مَدِينة 🢠 مُدُن cities 🢠 city	حِمار 🢠 حُمُر  donkeys 🢠 donkey	فُعُل
صَنَم 🢠 أَصْنام   idols 🢠 idol	سُوق 🢠 أَسْواق markets 🢠 market	أَفْعال
قارئ 🢠 قُرّاء readers 🢠 reader	طالِب 🢠 طُلاّب students 🢠 student	فُعّال
كاتِب 🢠 كَتَبة writers 🢠 writer	طالِب 🢠 طَلَبة   students 🢠 student	فَعَلة 🢠 variation of فُعّال
طَعام 🢠 أَطْعِمة foods 🢠 food	زَمان 🢠 أَزْمِنة   times 🢠 time	أَفْعِلة
بَنْك bank 🢠 بُنُوك banks 🢠 bank	فَنّ 🢠 فُنُون arts 🢠 art	فُعُول
سُنّة 🢠 سُنَن traditions 🢠 tradition	صُورة 🢠 صُوَر pictures 🢠 picture	فُعَل
ظِلّ 🢠 ظِلال  shadows🢠 shadow	صَغِير 🢠 صِغار small	فِعال
حُوت 🢠 حِيتان whales 🢠 whale	جار 🢠 جِيران neighbours 🢠 neighbour	فِعْلان
فارِس 🢠 فُرْسان knights 🢠 knight	بِلاد 🢠 بُلْدان countries 🢠 country	فُعْلان
شَهْر 🢠 أَشْهُر  months 🢠 month	حَرْف 🢠 أَحْرُف letters 🢠 letter	أَفْعُل
نَخْل 🢠 نَخِيل palm trees 🢠 palm tree	عَبْد 🢠 عَبيد slaves 🢠 slave	فَعِيل
قاعدة 🢠 قَواعِد rules 🢠 rule	قامُوس 🢠 قَوامِيس dictionnaries 🢠 dictionary	فَواعيل / فَواعِل (diptote)
قَصِيدة 🢠 قَصائِد poems 🢠 poem	جَزِيرة 🢠 جَزائِر  islands 🢠 island	فَعائِل (diptote)
أُنْمُلة 🢠 أَنامِل finger tips 🢠 finger tip	أُسْبوع 🢠 أَسابِيع weeks 🢠 week	أَفاعِيل / أفاعِل (diptote)
تَجْرِبة 🢠 تَجارِب experiences 🢠 experience	تِمْثال 🢠 تَماثِيل statues 🢠 statue	تَفاعِيل / تَفاعِل (diptote)
مِقْدار 🢠 مَقادِير amounts 🢠 amount	مِنْقار 🢠 مَناقِير beaks 🢠 beak	مَفاعِيل (diptote)
مَذْهَب 🢠 مَذاهِب doctrines 🢠 doctrine	مَطْعَم 🢠 مَطاعِم restaurants 🢠 restaurant	مَفاعِل (diptote)
نَبِيّ 🢠 أَنْبياء prophets 🢠 prophet	صَدِيق 🢠 أَصْدِقاء friends 🢠 friend	أَفْعِلاء (diptote)
عالِم 🢠 عُلَماء  scholars  🢠  scholar	أَمِير 🢠 أُمَراء  princes 🢠 prince	فُعَلاء (diptote)
فَتْوى 🢠 فَتاوى advisory opinions 🢠 advisory opinion	سَكْران 🢠 سُكارى drunk	فُعالى / فَعالى (indeclinable)
أَحْمَق 🢠 حَمْقى fools 🢠 fool/foolish	مَرِيض 🢠 مَرْضى sick	فَعْلى (indeclinable)
مَزيّة 🢠 مَزايا advantages 🢠 advantage	خَطِيئة 🢠 خَطايا sins 🢠 sin	فَعالا (indeclinable)

Quadriliteral root / الرُباعِي

Examples (أَمْثِلة)		Plural pattern (الوَزْن)
ثَعْلَب 🢠 ثَعالِب foxes 🢠 fox	عُصْفور 🢠 عَصافِير little birds 🢠 little bird	فَعاليل / فَعالِل (diptote)
مَغْرِبي 🢠 مَغارِبة Moroccans 🢠 Moroccan	أُسْتاذ 🢠 أَساتِذة professors 🢠 professor	فَعالِلة (diptote)

Note: Words with 5 roots letters are very rare and originally do not come from the Arabic language. They lose one root letter in the plural form:

بَرْنامَج 🢠 بَرامِج

programs 🢠 program

📢 Arabic learners are not expected to memorize those patterns, native speakers do not themselves. The aim of this section is to give an overview of the different broken patterns you can find in Arabic. The best practice, after all, is to always memorize both the singular and plural forms when learning a new word. As the student continues to expose himself to the language, most of these occurrences will be memorized organically and almost subconsciously. 

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