According to traditional Arabic grammar, every verb which is in the active voice must have a subject fāʿil (فاعل). If the subject of a verb is implicit through inflection, then an explicit subject is added to the dependency graph as a hidden subject pronoun. Similarly every verb in the passive voice must be linked to another node through a dependency relation called nāib fāʿil (نائب فاعل). This represents the subject of a passive verb, and if not already a word in the verse, must also always be present by adding a hidden subject pronoun.
A verb can optionally take an object mafʿūl bihi (مفعول به) and ditransitive verbs take a subject and two objects. The subject and objects of a verb can be other words, or they can be pronoun suffixes fused to the same verb. Regardless of which morphological segments take the role of subject and object, the subject must always be in the nominative case marfūʿ (مرفوع), and any objects must always be in the accusative case manṣūb (منصوب).
Fig 1. below lists hidden subject pronouns by verb inflection:
|Verb Inflection||Hidden Subject Pronoun|
|First person singular||أَنَا|
|First person plural||نَحْنُ|
|Second person masculine singular||أَنتَ|
|Second person masculine plural||أَنتُم|
|Third person masculine singular||هُوَ|
|Third person feminine singlar||هِىَ|
|Third person masculine plural||هُم|
Fig 1. Hidden subject pronouns.
The following dependency graph shows a syntactic analysis for verse (99:1). The passive verb has a dependency relation for nāib fāʿil (نائب فاعل):
(with) its earthquake,
Fig 2. Passive verb subject representative (99:1).
The next verse (99:2) has an active verb with a fāʿil (فاعل) dependency relation:
And brings forth
Fig 3. Verb subject dependency relation (99:2).