Arabic verbs

Arabic verbs (فِعْل fiʻl; pl. أَفْعَال afʻāl), like the verbs in other Semitic languages, and the entire vocabulary in those languages, are based on a set of two, three, four and also five (but mainly three) consonants called a root (triliteral or quadriliteral according to the number of consonants). The root communicates the basic meaning of the verb, e.g. k-t-b 'write', q-r-ʼ 'read', ʼ-k-l 'eat'. Changes to the vowels in between the consonants, along with prefixes or suffixes, specify grammatical functions such as person, gender, number, tense, mood, and voice.

Various categories are marked on verbs:

Weakness is an inherent property of a given verb determined by the particular consonants of the verb root (corresponding to a verb conjugation in Classical Latin and other European languages), with five main types of weakness and two or three subtypes of each type.

Arabic grammarians typically use the root f-ʻ-l to indicate the particular shape of any given element of a verbal paradigm. As an example, the form yutakātabu 'he is corresponded (with)' would be listed generically as yutafāʻalu, specifying the generic shape of a strong Form VI passive verb, third-person masculine singular present indicative.

The maximum possible total number of verb forms derivable from a root — not counting participles and verbal nouns — is approximately 13 person/number/gender forms; times 7.385 tense/mood combinations, counting the sa- future (since the moods are active only in the present tense, and the imperative has only 5 of the 13 paradigmatic forms); times 17 form/voice combinations (since forms IX, XI-XV exist only for a small number of stative roots, and form VII cannot normally form a passive), for a total of 1,632. Each of these has its own stem form, and each of these stem forms itself comes in numerous varieties, according to the weakness (or lack thereof) of the underlying root.

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