Arabic builds most numbers from 21 to 99 in the order unit + و + decade: ثلاثة وعشرون is literally “three and twenty.” This is the reverse of English word order, but it does not reverse the written digits: ٢٣ and 23 both still have 2 in the tens place and 3 in the units place.
The two components do different jobs. The unit carries the gender behavior associated with one, two, or three through nine; the decade carries a case ending like a sound masculine plural. The counted noun after the complete number is singular accusative, regardless of whether the number is 21, 38, or 99. Learn the entire number phrase as one governed structure.
If the lower ranges are not yet secure, review Numbers 0–10 in Isolation before combining their gender patterns with the decades.
The basic structure
The decades عشرون، ثلاثون، أربعون، خمسون، ستون، سبعون، ثمانون، تسعون combine with a preceding unit through و “and.” The unit comes first in speech and writing.
| Value | With a masculine noun | With a feminine noun | Counted noun |
|---|---|---|---|
| 21 | واحد وعشرون طالبا | إحدى وعشرون طالبة | singular accusative |
| 22 | اثنان وعشرون طالبا | اثنتان وعشرون طالبة | singular accusative |
| 23–29 | ثلاثة...تسعة وعشرون طالبا | ثلاث...تسع وعشرون طالبة | singular accusative |
| 30, 40...90 | ثلاثون...تسعون طالبا | ثلاثون...تسعون طالبة | singular accusative |
حضر واحد وعشرون طالبا محاضرة اليوم.
ḥaḍara wāḥidun wa-ʿishrūna ṭāliban muḥāḍarata l-yawm.
Twenty-one male students attended today's lecture.
وصلت إحدى وعشرون حافلة إلى المحطة.
waṣalat ʾiḥdā wa-ʿishrūna ḥāfilatan ʾilā l-maḥaṭṭa(h).
Twenty-one buses arrived at the station.
The subject number phrase is nominative in both sentences, hence عشرون. The feminine unit إحدى does not display a short case ending, but واحد does: واحدٌ here. The noun remains singular accusative: طالبًا، حافلةً.
One and two agree; three through nine show polarity
In 21, the unit agrees with the counted noun: واحد with a masculine noun and إحدى with a feminine noun. واحدة وعشرون is also found, especially where the number is treated more transparently as “one and twenty,” but إحدى وعشرون is the standard compact form taught for feminine counted nouns in careful MSA.
In 22, both gender and case are visible: اثنان/اثنين with a masculine noun and اثنتان/اثنتين with a feminine noun. For 23–29, the unit follows the familiar 3–9 polarity rule: the form with ـة counts a masculine noun, while the form without it counts a feminine noun.
قابلت اثنين وعشرين مهندسا بعد الاجتماع.
qābaltu thnayni wa-ʿishrīna muhandisan baʿda l-ijtimāʿ.
I met twenty-two engineers after the meeting.
راجعت اثنتين وثلاثين صفحة في المساء.
rājaʿtu thnatayni wa-thalāthīna ṣafḥatan fī l-masāʾ.
I reviewed thirty-two pages in the evening.
تحدثت مع ثلاثة وعشرين طبيبا.
taḥaddathtu maʿa thalāthatin wa-ʿishrīna ṭabībā.
I spoke with twenty-three doctors.
The last example makes an important separation visible. مع makes both coordinated numeral parts genitive: ثلاثةٍ وعشرين. It does not make the specification طبيبًا genitive; the counted noun after 11–99 remains singular accusative.
Case appears on both coordinated parts
The decades decline like sound masculine plurals: nominative ـون and accusative/genitive ـين. The unit is a separate conjunct and takes the same syntactic case. Full endings are clearest in careful reading and in grammar-focused contexts; ordinary formal speech often suppresses short endings, especially at a pause, but the written syntax remains the same.
| Case | Masculine 23 | Feminine 35 |
|---|---|---|
| nominative | ثلاثة وعشرون طالبا | خمس وثلاثون طالبة |
| accusative | ثلاثة وعشرين طالبا | خمسا وثلاثين طالبة |
| genitive | ثلاثة وعشرين طالبا | خمس وثلاثين طالبة |
The unvocalized form of ثلاثة looks the same in all three rows; fully vocalized reading supplies ثلاثةُ، ثلاثةَ، ثلاثةِ. By contrast, عشرون/عشرين makes the nominative–oblique contrast visible even without vowel marks.
فازت سبع وثلاثون باحثة بمنح جديدة.
fāzat sabʿun wa-thalāthūna bāḥithatan bi-minaḥin jadīda(h).
Thirty-seven female researchers won new grants.
شملت الدراسة خمسا وستين مدينة.
shamilati d-dirāsatu khamsan wa-sittīna madīna(h).
The study covered sixty-five cities.
باحثة and مدينة are feminine, so their units are سبع and خمس without ـة. In the second sentence, the entire number phrase is a direct object, so both خمسًا and ستين are accusative.
The special unit eight with feminine nouns
The polarity form for eight before a feminine counted noun is the defective numeral ثماني. Because the unit and decade are coordinated rather than joined in iḍāfa, indefinite ثماني loses its final ي in the nominative and genitive and replaces it with tanwīn: ثمانٍ وعشرون طالبةً and مع ثمانٍ وعشرين طالبةً. The accusative retains the ي and is commonly written ثمانيًا وعشرين طالبةً. With a masculine counted noun, regular ثمانية appears instead: ثمانية وعشرون يومًا.
حضرت ثمان وعشرون طالبة جلسة التدريب.
ḥaḍarat thamānin wa-ʿishrūna ṭālibatan jalsata t-tadrīb.
Twenty-eight female students attended the training session.
قابلت ثمانيا وعشرين موظفة بعد الاجتماع.
qābaltu thamāniyan wa-ʿishrīna muwaẓẓafatan baʿda l-ijtimāʿ.
I met twenty-eight female employees after the meeting.
Decades without a unit
A bare decade has no gender contrast. عشرون counts both masculine and feminine nouns, and the specification is still singular accusative.
بقي ثلاثون مقعدا في القاعة.
baqiya thalāthūna maqʿadan fī l-qāʿa(h).
Thirty seats remained in the hall.
أضافت الشركة أربعين وظيفة هذا العام.
ʾaḍāfati sh-sharikatu ʾarbaʿīna waẓīfatan hādhā l-ʿām.
The company added forty jobs this year.
Do not choose أربعون or أربعين from the gender of وظيفة. The choice is case: أربعين is accusative because it is the object of أضافت.
Reading digits, prices, and measurements
When Arabic digits occur inside right-to-left text, read their place value normally. ٤٧ is forty-seven, but Arabic says the unit first: سبعة وأربعون. A screen may visually position punctuation in a surprising way, yet neither the digits nor the spoken value reverse.
سعر التذكرة ٤٧ دولارا.
siʿru t-tadhkirati sabʿatun wa-ʾarbaʿūna dūlārā.
The ticket costs 47 dollars.
قطع الفريق ٢٦ كيلومترا في يوم واحد.
qaṭaʿa l-farīqu sittatan wa-ʿishrīna kīlūmitran fī yawmin wāḥid.
The team covered 26 kilometers in one day.
In the first, masculine دولار selects unit سبعة. In the second, masculine كيلومتر selects ستة. Both specifications are singular accusative.
Common Mistakes
Extending one gender rule across the whole number
❌ حضر ثلاث وعشرون طالبا.
Incorrect — طالب is masculine, so the unit three must use the polarity form ثلاثة.
✅ حضر ثلاثة وعشرون طالبا.
ḥaḍara thalāthatun wa-ʿishrūna ṭālibā.
Twenty-three students attended.
Using a plural noun after 21–99
❌ قرأت خمسة وعشرين كتبا.
Incorrect — after 11–99, the counted noun is singular accusative.
✅ قرأت خمسة وعشرين كتابا.
qaraʾtu khamsatan wa-ʿishrīna kitābā.
I read twenty-five books.
Reversing the digit value
❌ الرقم ٢٤ يعني اثنين وأربعين.
Incorrect — ٢٤ is 24, not 42; right-to-left text does not reverse place value.
✅ الرقم ٢٤ يعني أربعة وعشرين.
ar-raqmu ʾarbaʿatun wa-ʿishrūna yaʿnī ʾarbaʿatan wa-ʿishrīn.
The number 24 means twenty-four.
Leaving the decade nominative in an object
❌ قابلت واحدا وثلاثون موظفا.
Incorrect — both coordinated parts are accusative in this direct-object phrase.
✅ قابلت واحدا وثلاثين موظفا.
qābaltu wāḥidan wa-thalāthīna muwaẓẓafā.
I met thirty-one employees.
Key Takeaways
- Build 21–99 as unit + و + decade, even though English says the decade first.
- One and two agree with the counted noun; units three through nine show gender polarity.
- The unit and decade share the phrase's syntactic case; decades use ـون in the nominative and ـين in the accusative and genitive.
- After every number from 11 through 99, use a singular accusative counted noun.
- Written digits keep their ordinary place value inside right-to-left Arabic text.
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Start learning Arabic →Related Topics
- The Decades 20–90A2 — Decline the decades like sound masculine plurals, keep them gender-invariant, and use a singular accusative counted noun.
- Hundreds, Thousands, Millions, and BillionsA2 — Build large Arabic numbers by treating hundred, thousand, million, and billion as noun-like heads with governed complements.
- Numbers 0–10 in IsolationA1 — Read, pronounce, and distinguish the citation and gender-paired forms of Arabic zero through ten before building counted-noun phrases.