Indeclinable Words and Local Iʿrāb | Arabic (Modern Standard) Grammar

Case is a property of syntactic position, not merely a vowel that you can see. Many extremely common Arabic words are indeclinable—traditional Arabic grammar calls them مبنيّ mabniyy, “built on a fixed form.” A demonstrative such as هذا does not acquire -u, -a, or -i, yet it can be a subject, direct object, or complement of a preposition.

To describe this, Arabic grammar uses local iʿrāb: a fixed word is “in a nominative, accusative, or genitive position” (في محل رفع / نصب / جر). The form stays stable while its job changes. This analysis is central to formal contemporary Modern Standard Arabic (formal) and is especially useful when reading fully parsed texts.

The case overview introduces the three syntactic cases before this page asks how they surface on fixed forms.

Three ways case can surface

Before looking at particular word classes, keep these three analyses separate:

Type	What happens	Example
Visible iʿrāb	The pronounced ending changes overtly.	مُدِيرٌ / مُدِيرًا / مُدِيرٍ
Estimated iʿrāb	The word is declinable, but its final phonological shape prevents the ordinary ending from appearing.	الْفَتَى with case estimated on final ى
Local iʿrāb	The word is indeclinable; its whole fixed form occupies a case position.	هَٰذَا as subject, object, or prepositional complement

Estimated case is not the same as local case. الفتى belongs to a declinable noun paradigm whose ending is phonologically hidden. هذا is fixed by lexical class. Pause is different from both: pausing may suppress an audible ending on a declinable word, but it does not make that word indeclinable.

💡

Ask two questions in order: “What syntactic position does this expression occupy?” and “Can this word class display that case by changing its ending?” The first determines case; the second determines whether the iʿrāb is visible, estimated, or local.

Demonstratives: one form, three positions

Most singular and plural demonstratives are indeclinable. هذا remains هذا across the following three-case set:

هذا تقرير مهم.

hādhā taqrīrun muhim.

This is an important report. (Hādhā is in a nominative position as the subject.)

قرأت هذا التقرير صباحا.

qaraʾtu hādhā t-taqrīra ṣabāḥā.

I read this report in the morning. (Hādhā is in an accusative position as part of the object phrase.)

وجدت المعلومة في هذا التقرير.

wajadtu l-maʿlūmata fī hādhā t-taqrīr.

I found the information in this report. (Hādhā is in a genitive position after fī.)

The demonstrative's final alif does not take a case vowel. The following noun, however, displays case visibly: تقريرٌ, التقريرَ, التقريرِ. Traditional parsing describes the demonstrative locally and analyzes the following definite noun as appositional or explanatory, matching the phrase's case.

Feminine هذه, distal ذلك / تلك, and the common plural هؤلاء behave similarly:

ناقشنا هذه المسألة في الاجتماع.

nāqashnā hādhihi l-masʾalata fī l-ijtimāʿ.

We discussed this issue at the meeting. (Hādhihi is locally accusative.)

تحدثت إلى هؤلاء الباحثين بعد الجلسة.

taḥaddathtu ʾilā hāʾulāʾi l-bāḥithīna baʿda l-jalsa(h).

I spoke to these researchers after the session. (Hāʾulāʾi is locally genitive.)

The final kasra heard in هؤلاءِ belongs to its fixed form; it does not prove genitive. The same pronunciation can appear in a nominative position: هؤلاءِ الباحثون “these are the researchers.” This is exactly why the analysis is called local.

The dual demonstratives are an exception

Do not overgeneralize “all demonstratives are fixed.” The dual forms show a nominative–oblique contrast: هذانِ / هاتانِ in the nominative and هذينِ / هاتينِ in the accusative or genitive (formal).

قابلت هذين الباحثين أمس.

qābaltu hādhayni l-bāḥithayni ʾams.

I met these two researchers yesterday. (Visible oblique marking on the dual demonstrative.)

Here the demonstrative does change form, so describing هذين as simply “locally accusative without visible case” would miss its visible dual inflection.

Independent and attached pronouns

Personal pronouns are indeclinable, but their series and attachment site help show their role. Independent subject pronouns normally occupy nominative positions:

هم مستعدون لبدء الاجتماع.

hum mustaʿiddūna li-badʾi l-ijtimāʿ.

They are ready to begin the meeting. (Hum is locally nominative.)

An attached pronoun can instead be an object or a complement of a preposition:

قابلتهم بعد الاجتماع.

qābaltuhum baʿda l-ijtimāʿ.

I met them after the meeting. (-hum is locally accusative as the direct object.)

تحدثت معهم بعد الاجتماع.

taḥaddathtu maʿahum baʿda l-ijtimāʿ.

I spoke with them after the meeting. (-hum is locally genitive after maʿa.)

The fixed pronominal element هم does not receive the regular noun endings. Its environment supplies the analysis: attached to a transitive verb, it is an object; attached to a preposition, it is genitive. Possessive suffixes are likewise locally genitive because they occupy the position of the second term of an iḍāfa:

هذا مكتبهم، وقد انتقلوا إليه أمس.

hādhā maktabuhum, wa-qadi ntaqalū ʾilayhi ʾams.

This is their office, and they moved into it yesterday. (-hum after the noun is locally genitive.)

English also changes some pronoun forms—they, them, their—but Arabic differs in joining many object and possessive pronouns directly to the preceding word. Do not look for a separate English-style word in every position.

💡

With an attached pronoun, use the host as your clue: verb + suffix usually gives a direct object, preposition + suffix gives a genitive complement, and noun + suffix gives a possessive second term that is locally genitive.

Relative pronouns and their clause roles

Singular الذي / التي and plural الذين are indeclinable. Their case comes from the role of the entire relative expression in the larger sentence:

وصل الذي أرسل الرسالة.

waṣala lladhī ʾarsala r-risāla(h).

The man who sent the message arrived. (Alladhī is locally nominative as subject of the main clause.)

قابلت الذي أرسل الرسالة.

qābaltu lladhī ʾarsala r-risāla(h).

I met the man who sent the message. (Alladhī is locally accusative as object of the main verb.)

تحدثت مع الذي أرسل الرسالة.

taḥaddathtu maʿa lladhī ʾarsala r-risāla(h).

I spoke with the man who sent the message. (Alladhī is locally genitive after maʿa.)

Nothing on الذي changes. The surrounding governor establishes the role. Inside the relative clause, a separate analysis applies. In traditional terms, أرسل contains an implicit subject pronoun referring back to الذي; that internal link does not change the relative pronoun's local case in the main clause.

As with demonstratives, the dual relative pronouns are a visible exception: nominative اللذانِ / اللتانِ contrasts with oblique اللذينِ / اللتينِ (formal). The common masculine plural الذين is fixed and must not be confused with dual اللذين merely because unvocalized text makes them similar.

Word order when endings cannot help

With declinable nouns, overt case can support marked word order. Indeclinables cannot provide that audible contrast, so neutral order, verb meaning, agreement, clitic position, and discourse context do more work.

قابل هذا ذاك في المؤتمر.

qābala hādhā dhāka fī l-muʾtamar.

This person met that person at the conference. (Neutral postverbal order: first the subject, then the object.)

Both demonstratives are fixed. Traditional analysis calls هذا locally nominative and ذاك locally accusative. Unlike قابل المديرُ الضيفَ, their final shapes cannot confirm the roles. A writer who fronts the object must supply enough context to prevent ambiguity; ordinary neutral order is clearer here.

Unvocalized reading therefore requires more than restoring endings. In قرأت هذا التقرير, the verb's argument structure, the demonstrative phrase, and the following noun all cooperate to identify an accusative object.

Definiteness, endings, and pause

Personal pronouns and demonstratives are inherently definite, and relative pronouns introduce definite relative descriptions. They do not take tanwīn. You also do not add the ordinary definite article to هذا or هو. The initial الـ in الذي belongs to the relative form and is not a detachable article that licenses case endings.

Because these words are fixed, connected speech does not add -u, -a, or -i according to their current role. Pause may affect ordinary phonetic details, but it does not explain their invariability. هذا is still hādhā before another word and at the end of an utterance.

Common Mistakes

1. Adding a visible noun-case vowel to an indeclinable demonstrative.

❌ قرأت هذا التقرير.

Incorrect: hādhā is locally accusative but does not take an added fatḥa.

✅ قرأت هذا التقرير.

qaraʾtu hādhā t-taqrīr.

I read this report.

2. Ignoring neutral word order when fixed forms cannot show the roles.

❌ قابل ذاك هذا.

Incorrect for the intended meaning ‘This person met that person’: in neutral order, this says that person met this person.

✅ قابل هذا ذاك.

qābala hādhā dhāk.

This person met that person. (Neutral subject-before-object order after the verb.)

3. Inventing a case ending at pause.

❌ هذا المدير.

Incorrect: pause or connection never gives hādhā an added nominative -u.

✅ هذا المدير.

hādhā l-mudīr.

This is the director. (Natural pause.)

4. Calling a fatḥa “accusative” without identifying the paradigm and governor.

❌ عملت في مدارس كثيرة.

Incorrect: the indefinite diptote madāris takes fatḥa after the preposition.

✅ عملت في مدارس كثيرة.

ʿamiltu fī madārisa kathīra(h).

I worked in many schools. (Madārisa is genitive despite the fatḥa.)

5. Letting verb mood change the case analysis of a pronoun subject.

❌ لن يأتي المدير اليوم.

Incorrect: lan makes the verb subjunctive but does not make its subject accusative.

✅ لن يأتي المدير اليوم.

lan yaʾtiya l-mudīru l-yawm.

The director will not come today. (The noun subject is nominative.)

The same analysis applies to an emphasized pronominal subject in لَنْ يَأْتِيَ هُوَ الْيَوْمَ lan yaʾtiya huwa l-yawma: هو is locally nominative, while لن governs only the mood of يأتي.

Key Takeaways

An indeclinable word can be nominative, accusative, or genitive by position without changing its form. Pronouns, most demonstratives, and most relative pronouns therefore receive local iʿrāb. Visible endings on nearby nouns, the governor, clitic attachment, agreement, neutral word order, and context reveal the role. Keep this separate from estimated case on declinable nouns and from the ordinary suppression of endings at pause.

Now practice Arabic

Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.

Start learning Arabic →