Compound Numbers
Numbers 11–99 are divided into Compound Numbers (11–19) and Conjoined Numbers (21–99). Unlike 3–10, these numbers require the counted noun to be singular and accusative (ending in -an).
How It Works
Counting in Arabic becomes more structured once you reach 11. Here are the three main categories:
1. Compound Numbers (11–19):
These consist of two parts joined together.
- 11 and 12: Both parts agree with the noun's gender (e.g., أحد عشر كتاباً).
- 13–19: The unit (3–9) has the opposite gender of the noun, while the 'ten' part matches the noun.
- Behavior of Ten: Note that while the standalone number ten follows gender polarity, it switches to matching the noun when it is part of a compound (11–19).
- Phonetic Note: The letter 'shīn' in the 'ten' component takes a fatḥa (عَشَرَ) with masculine nouns and a sukūn (عَشْرَة) with feminine nouns.
- Both parts are fixed with a fatḥa ending (mabnī), except for the '2' in 12.
2. The Decades (20, 30, ... 90):
These are called Uqūd. They are gender-neutral but change their ending based on case (-ūn for nominative, -īn for accusative/genitive).
3. Conjoined Numbers (21–99):
These use the conjunction wa (and) between the unit and the decade.
- The unit comes first: 'Five and twenty' instead of 'Twenty-five'.
- Gender Rules: Units 1 and 2 agree with the noun's gender. For feminine nouns, the unit 'one' takes the specific form إحدى (iḥdā) rather than واحدة. Units 3–9 follow gender polarity (opposite of the noun).
- Case and Tanwīn: Unlike compound numbers, the unit in conjoined numbers declines normally and takes tanwīn. The decade follows the unit's case.
The Counted Noun:
For all numbers 11–99, the noun must be in the singular accusative form (e.g., كتاباً, شجرةً).
Examples (6)
- رأيتُ أحدَ عشرَ كوكباً.
I saw eleven stars.
Word by Word: I saw one ten star.
For 11, both 'one' and 'ten' match the masculine noun 'star'. Note the fatḥa on the shīn in 'ashara.
- في الصفِ خمسَ عشرةَ طالبةً.
In the class are fifteen (female) students.
Word by Word: In the class five ten student.
For 15, the unit (five) is masculine to oppose the feminine noun, but 'ten' matches the feminine noun. Note the sukūn on the shīn in 'ashrata.
- قرأتُ ثلاثةً وعشرينَ كتاباً.
I read twenty-three books.
Word by Word: I read three and twenty book.
The unit 'three' is feminine because 'book' is masculine. In conjoined numbers, the unit takes tanwīn.
- نجحَ خمسةٌ وتسعونَ طالباً.
Ninety-five students passed.
Word by Word: Succeeded five and ninety student.
The unit 'five' is feminine (khamsun) to oppose the masculine 'student'. The decade 'ninety' follows the unit's case.
- اشتريتُ سبعاً وأربعينَ مجلةً.
I bought forty-seven magazines.
Word by Word: I bought seven and forty magazine.
Since 'magazine' is feminine, the unit 'seven' is masculine (sab'an). Both parts are in the accusative case.
- وصلَ واحدٌ وعشرونَ مسافراً.
Twenty-one travelers arrived.
Word by Word: Arrived one and twenty traveler.
For conjoined numbers ending in 1 or 2, the unit agrees with the noun's gender instead of showing polarity.
Common Mistakes
Using a plural noun after numbers 11–99.
عندي عشرون كتباً.عندي عشرون كتاباً.Unlike numbers 3–10 which take a plural, numbers 11–99 must be followed by a singular noun in the accusative case.
Matching the unit's gender to the noun for numbers 13–99 (excluding 1 and 2).
خمس وعشرون رجلاًخمسةٌ وعشرون رجلاًFor units 3–9, the gender must be the opposite of the noun. Since 'man' is masculine, the unit 'five' must be feminine.
Forgetting to change the decade ending in accusative/genitive positions.
سلمتُ على ثلاثون طالباً.سلمتُ على ثلاثينَ طالباً.The decades (20–90) behave like sound masculine plurals. After a preposition like 'على', the ending must change from -ūn to -īn.
How It Connects
Learn This First
To learn compound numbers (21-99), you must first understand the basic counting units (1-9), the decade numbers (20, 30, etc.), and how to use the conjunction 'wa' to link them. It also requires familiarity with how numbers 11-19 are structured as a foundation for multi-part number systems.
- Numbers Eleven to Nineteen
Compound numbers (21-99) build upon the logic of combining units and tens established in the teens.
Level 2 - Tens From Twenty to Ninety
The 'tens' component of compound numbers (e.g., twenty, thirty) must be understood as they form the second part of the construction.
Level 2 - و (العطف)And
The conjunction 'wa' (and) is the essential connector used to join the unit and the decade in these numbers.
Level 1
Related Patterns
- Counting Three to Ten
Contrast these rules with 3–10, which require a plural genitive noun instead of a singular accusative one.
Level 2 - Numbers Flip Their Gender
This explains the core logic of gender polarity (units 3–9) used within compound and conjoined numbers.
Level 2 - The Clarifying Noun
The counted noun in 11–99 is grammatically classified as a 'tamyīz' (clarifying noun) in the accusative case.
Level 3 - How Regular Masculine Plurals Change
The decades (20–90) follow the same case ending rules as regular masculine plurals.
Level 3
Practice Compound Numbers in Bubblegum
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