Arabic verbs (i.e. finite verbs) are conjugated for:
- Aspect: perfective & imperfective.
- Voice: active & passive.
- Person: 1ˢᵗ, 2ⁿᵈ & 3ʳᵈ persons.
- Number: singular, dual & plural.
- Gender: masculine & feminine.
- Mood: indicative, energetic, subjunctive, jussive, imperative & energetic imperative.
Conjugation for aspect and voice is done through vowel mutation, that is, changing vowels in the verb stem. Conjugation for person, number, gender and mood is done by altering a suffix and a prefix attached to the verb stem without changing the stem itself, except for irregularly conjugated verbs.
Conjugating verbs through vowel mutation exists in English. Consider the difference between eat and ate. However, while in English this type of conjugation is limited to a small number of verbs, all verbs in Arabic are conjugated this way for aspect and voice.
English has no limitation on the possible shapes of verb stems: there is an infinite number of possible stem shapes. In Arabic, however, there is a limited number of possible stem shapes. In total, there is about 25 types of verb stems in Classical Arabic, but many of them are rare or vestigial. The commonly used ones are 13 types, 10 triradical and 3 quadriradical. To be able to conjugate verbs for aspect and voice, you need to be familiar with these 13 stem types and know how their vowels mutate.
The simplest type of verb stems is given the number Ⅰ. (It is also called the G-stem for the German Grundstamm “basic stem.”)
It looks as follows.
|Stem Ⅰ (G-stem)|
The ending –a in the perfective form, and the prefix y– and the ending –u in the imperfective form are all inflectional parts. They do not belong to the stem. They mark the above forms as 3rd person masculine singular conjugations. Verbs are cited in this particular conjugation because it is the simplest one.
Thus, the actual stems are faʕVl– (perfective) and –afʕVl– (imperfective). These stems have a variable short vowel represented by the symbol V. We will call this vowel the theme vowel. A theme vowel exists in all types of verb stems and not only Stem Ⅰ. It is defined as the vowel before the last consonant of the stem. Its value was originally determined by the verb’s transitivity, i.e. the number of objects the verb can govern. In imperfective verbs, the theme vowel usually has the value a in intransitive verbs and u or i in transitive verbs. An opposite distribution is found in perfective verbs.
Another variable vowel is the vowel at the beginning of the imperfective stem, which we will call the prefix vowel. In Stem Ⅰ this vowel always has the value a.
Perfective vs. imperfective
A tense is a point in time used as a reference for an event indicated by a verb. An aspect is a temporal relation between a verb’s event and its tense. For example, the English perfect aspect can be used in conjunction with any point in time (any tense) to indicate that the event is finished at that point and has relevance at it. The progressive/continuous aspect indicates that the event is progressing at the referential point in time.
Unlike English, the Arabic verbal system does not mark tenses. It only marks two aspects, the first called the perfective (in Arabic the past الْماضِيْ ) and the second called the imperfective (in Arabic usually called the similar الْمُضارِعُ ). The perfective aspect simply indicates that the verb’s event is finished at the referential point in time, and the imperfective aspect simply indicates that the verb’s event is ongoing/unfinished at that point. The referential point in time is not indicated by the verb itself but by other supplementary words in the sentence.
This means that the perfective faʕala فَعَلَ can correspond to any of the following in English:
- he did
- he had done
- he has done
- he will have done
The imperfective yafʕalu يَفْعَلُ can correspond to any of the following in English:
- he used to do
- he was doing
- he does
- he is doing
- he will do
- he will be doing
In order to know what tense is meant by the speaker, we need to look at the sentence as a whole, or at the context. There are no fixed formulae for expressing the different tenses as in English. However, because the perfective verb is most commonly used for the past tense, this is considered its default tense (hence its Arabic name, the past). The imperfective verb is by default a present/future verb because these are its most common tenses.
Action vs. non-action
The Arabic verbal system marks a distinction between:
- Action verbs, i.e. verbs denoting actions (also called dynamic or fientive/fientic).
- Non-action verbs (also called stative).
Furthermore, non-action verbs are differentiated into:
- State verbs: verbs denoting being or becoming in a temporary state.
- Quality verbs: verbs denoting having or gaining a permanent quality.
Stem Ⅰ action verbs often (not always) have a as the theme vowel in the perfective, and u or i as the theme vowel in the imperfective.
|Stem Ⅰ (G-stem)|
|he wrote||he writes|
|he ate||he eats|
|he killed||he kills|
|he broke (tr.)||he breaks (tr.)|
If the second or third radical of an action verb is a guttural sound (ʔ, h, ħ, ʕ, x, ɣ), the verb will often have the theme vowel a in the imperfective due to an old phonetic shift i/u > a near gutturals.
|Stem Ⅰ (G-stem)|
|he did||he does|
|he wounded||he wounds|
|he cut||he cuts|
|he gathered||he gathers|
|he made||he makes|
Stem Ⅰ state verbs often have i as the theme vowel in the perfective, and a as the theme vowel in the imperfective.
|Stem Ⅰ (G-stem)|
|he was/became sound||he is/becomes sound|
|he was/became sad||he is/becomes sad|
|he was/became angry||he is/becomes angry|
|he was/became sick||he is/becomes sick|
Stem Ⅰ quality verbs have u as the theme vowel both in the perfective and imperfective.
|Stem Ⅰ (G-stem)|
|he was/became big||he is/becomes big|
|he was/became small||he is/becomes small|
|he was/became difficult||he is/becomes difficult|
|he was/became easy||he is/becomes easy|
Eventive vs. non-eventive
Non-action verbs can mean either being something or becoming something. (Verbs with the second meaning are called inceptive or inchoative.) For example, the state verb taʕiba, yatʕabu تَعِبَ، يَتْعَبُ can mean either “be tired” or “become tired.”
To become something is an event, but to be something is not. Only verbs indicating an event, whether action verbs or non-action verbs with the meaning of becoming something, can have a temporal meaning. Verbs that simply indicate being something do not indicate any time-related meaning. Thus, the verb taʕiba means simply “he is tired” when it is used as a non-eventive verb, but it has a perfective meaning “he has become tired,” “he became tired,” etc. when used as an eventive verb.
The non-eventive meaning of non-action verbs is common in Classical Arabic but rare in modern Arabic. The modern spoken vernaculars use predicative adjectives to express this meaning.