When discussing standings in a tournament or a sequence of events, you will need ordinal numbers. To form ordinals from eleventh to nineteenth, Arabic uses a two-part compound number.
Let's first look at an important noun you will use frequently when discussing rankings:
Eleventh and Twelfth
The masculine ordinals for 11th and 12th consist of a first part ending in a long ي followed by the word عشر. Because they function as adjectives, they directly follow the noun they modify.
Thirteenth through Nineteenth
For the 13th to the 19th, the first part is the standard ordinal number (الثالث, الرابع, and so on), followed by عشر.
Indeclinable Endings (مبني على فتح الجزأين)
Usually, an adjective changes its case ending to match the noun it modifies (taking a ضمة, فتحة, or كسرة). However, compound ordinal numbers from 11th to 19th are indeclinable—their vowel endings are locked and do not change.
For numbers 13th to 19th, both parts of the compound end in a fixed فتحة regardless of their grammatical role in the sentence. This locked state is known as مبني على فتح الجزأين. For 11th and 12th, the second part (عشر) maintains this fixed فتحة.
Even after prepositions like في or إلى—which normally force a word to take a كسرة—these compound ordinals stubbornly keep their fixed endings. Likewise, they do not take a ضمة when describing the subject of a sentence.
Notice how the numbers remain unchanged in the following sentences, despite being in genitive or nominative positions:
Seeing the endings
This course writes Arabic the way books and newspapers print it, without the short-vowel marks, so the ending this lesson is about is something you hear in the audio but never see in the drills. Here are some of them with every vowel written out:
| as written | fully vocalized | position |
|---|
| حقق الفريق المركز الحادي عشر في المسابقة. | حَقَّقَ الفَرِيقُ المَرْكَزَ الحَادِيَ عَشَرَ فِي المُسَابَقَةِ. | object |
| هذا هو اليوم الثالث عشر من التدريب. | هَذَا هُوَ اليَوْمُ الثَّالِثَ عَشَرَ مِنَ التَّدْرِيبِ. | predicate (nominative) |
| انسحبت فاطمة في الأسبوع الثامن عشر. | اِنْسَحَبَتْ فَاطِمَةُ فِي الأُسْبُوعِ الثَّامِنَ عَشَرَ. | after في (genitive) |
The noun in front of the ordinal changes its ending (المَرْكَزَ, اليَوْمُ, الأُسْبُوعِ), but the ordinal does not: both halves keep their fatha, الثَّالِثَ عَشَرَ, الثَّامِنَ عَشَرَ. In الحادي عشر and الثاني عشر the ي may also be read without a vowel: الثَّانِي عَشَرَ.
