Quadriliteral Form IV verbs (افْعَلَلَّ)

Quadriliteral Form IV (افعلل)

While most Arabic verbs are built on three-letter roots, some have four. These four-letter (quadriliteral) roots have their own set of derived forms. One of the rarest but most expressive is Form IV, which follows the pattern افْعَلَلَّ in the past tense.

These verbs typically express a strong physical reaction, an intense emotional state, or a gradual outcome—making them perfect for discussing mental health, processing trauma, or overcoming anxiety. They are almost always intransitive, meaning they describe a state rather than an action done to a direct object.

You can recognize this form by the added Alif (ا) at the beginning and the shadda (doubling) on the final root letter.

In the present tense, the initial Alif drops, and the pattern shifts to يَفْعَلِلُّ, while keeping the doubled final consonant.

Conjugating the Doubled Letter

Because the final root letter in this form is doubled by a shadda (like the ن in اطمأنَّ), you must separate that double letter when conjugating in the past tense for pronouns that add a consonant suffix—such as "I" (تُ) or "we" (نَا).

Notice how the verb اطمأنَّ (to feel reassured) separates into اطمأننت when conjugated for "I":

Expressing Outcomes and Reactions

Other common verbs in this form describe fading outcomes or visceral reactions, such as fading away (اضمحل) or feeling disgusted (اشمأز). Because these verbs focus on states, they are often paired with gradual processes or strong emotional shifts.