Form VI combines initial t with the long ā of Form III: تَفَاعَلَ in the perfect, يَتَفَاعَلُ in the imperfect, and تَفَاعُل as its regular verbal noun. Many Form VI verbs describe two or more participants acting toward one another, while another important group describes a process unfolding or changing by degrees. Neither meaning is guaranteed by the pattern alone; the Arabic verb-system overview shows where derived Forms sit within finite inflection.
The central example is تَعَاوَنَ — يَتَعَاوَنُ — تَعَاوُنًا “cooperate,” root ع-و-ن. It commonly selects مع for a partner and على for a task or goal.
The principal-part pattern
| Environment | Pattern | ع-و-ن |
|---|---|---|
| perfect, 3 m.sg. | تَفَاعَلَ | تَعَاوَنَ |
| imperfect indicative, 3 m.sg. | يَتَفَاعَلُ | يَتَعَاوَنُ |
| imperative, 2 m.sg. | تَفَاعَلْ | تَعَاوَنْ |
| verbal noun | تَفَاعُل | تَعَاوُن |
Like Form V, Form VI begins with a real t, not hamzat al-waṣl. The imperfect adds the person prefix before that t: يـ + تعاون = يتعاون. The long ā comes after the first radical. Form VI can therefore be understood structurally as t- plus the Form III shape, but the relationship between an actual Form III verb and its Form VI relative must be checked in the lexicon.
تعاون المركز مع الجامعة على تنظيم المؤتمر.
taʿāwana l-markazu maʿa l-jāmiʿati ʿalā tanẓīmi l-muʾtamar.
The center cooperated with the university to organize the conference.
يتعاون الأطباء والممرضات في متابعة الحالات الصعبة.
yataʿāwanu l-ʾaṭibbāʾu wal-mumarriḍātu fī mutābaʿati l-ḥālāti ṣ-ṣaʿba.
The doctors and nurses cooperate in monitoring difficult cases. (Singular verb before a compound plural subject.)
Reciprocal meaning and grammatical participants
تَبَادَلَ — يَتَبَادَلُ — تَبَادُلًا “exchange” (root ب-د-ل) normally takes the things exchanged as a direct object. تَفَاوَضَ — يَتَفَاوَضُ — تَفَاوُضًا “negotiate” (root ف-و-ض) often uses مع for the other party and حول or بشأن for the issue. The reciprocal relationship can be distributed across a plural subject or between a singular subject and a prepositional complement.
تبادلت الباحثتان الملاحظات قبل نشر الدراسة.
tabādalati l-bāḥithatāni l-mulāḥaẓāti qabla nashri d-dirāsa.
The two female researchers exchanged comments before publishing the study. (Singular verb in VSO.)
الباحثتان تبادلتا الملاحظات عبر المنصة الآمنة.
al-bāḥithatāni tabādalatā l-mulāḥaẓāti ʿabra l-minaṣṣati l-ʾāmina.
The two female researchers exchanged comments through the secure platform. (Subject-first dual agreement.)
These sentences describe the same reciprocal event. Their verb forms differ because neutral VSO normally uses a singular verb before an explicit dual subject, whereas subject-first order requires full dual agreement.
تفاوض المندوب مع الشركة حول شروط العقد.
tafāwaḍa l-mandūbu maʿa sh-sharikati ḥawla shurūṭi l-ʿaqd.
The delegate negotiated with the company about the contract terms.
A singular subject does not cancel reciprocal semantics: المندوب is one party, while الشركة after مع is the other. Conversely, a plural subject does not force a reciprocal interpretation if the lexical verb has another meaning.
Gradual and cumulative change
Form VI also contains many verbs of change by degrees. تَزَايَدَ — يَتَزَايَدُ — تَزَايُدًا “increase progressively” (root ز-ي-د) and تَنَاقَصَ — يَتَنَاقَصُ — تَنَاقُصًا “decrease progressively” (root ن-ق-ص) do not mean that participants increase one another. The pattern presents a developing process, but adverbs and context tell the reader whether the change is slow, sharp, regular, or temporary.
تزايد الطلب على النقل العام خلال الصيف.
tazāyada ṭ-ṭalabu ʿalā n-naqli l-ʿāmmi khilāla ṣ-ṣayf.
Demand for public transport increased over the summer.
تناقصت الاحتياطيات خلال الأشهر الثلاثة الماضية.
tanāqaṣati l-iḥtiyāṭiyyātu khilāla l-ʾashhuri th-thalāthati l-māḍiya.
The reserves decreased over the past three months. (Nonhuman plural with feminine-singular agreement.)
English often uses a simple verb plus an adverb—“increased gradually.” Arabic can lexicalize the developmental perspective in تزايد, although زاد may also mean “increase.” The two are not interchangeable in every sentence; genre and collocation matter.
Lexical meanings can leave the prototype
تَجَاهَلَ — يَتَجَاهَلُ — تَجَاهُلًا “ignore; deliberately act as if unaware” (root ج-ه-ل) is Form VI, but translating it as “be mutually ignorant” would be wrong. It is transitive and takes the ignored person, fact, or warning directly. تَنَاوَلَ — يَتَنَاوَلُ — تَنَاوُلًا can mean “take,” “consume,” or “address a topic,” depending on its object.
تجاهلت الإدارة التحذيرات المتكررة في التقرير.
tajāhalati l-ʾidāratu t-taḥdhīrāti l-mutakarrirata fī t-taqrīr.
The administration ignored the repeated warnings in the report.
تناولت الدراسة أثر الجفاف في الهجرة الداخلية.
tanāwalati d-dirāsatu ʾathara l-jafāfi fī l-hijrati d-dākhiliyya.
The study addressed the effect of drought on internal migration. (Academic register.)
The second example does not mean that a study physically “took” the effect. Formal prose commonly uses تناولت الدراسة موضوعًا for “the study addressed a topic.” This is why derived-Form labels cannot replace real collocations.
Perfect, imperfect, and mood
The imperfect stem يتعاونـ takes ordinary mood marking: indicative يتعاونُ, subjunctive يتعاونَ after لن, and jussive يتعاونْ after لم. The perfect has agreement suffixes such as تعاونتْ، تعاونا، تعاونوا.
| Subject/environment | Form |
|---|---|
| هو, perfect | تَعَاوَنَ |
| هي, perfect | تَعَاوَنَتْ |
| هما, perfect | تَعَاوَنَا |
| هم, imperfect indicative | يَتَعَاوَنُونَ |
| after لن, 3 m.sg. | لَنْ يَتَعَاوَنَ |
| after لم, 3 m.sg. | لَمْ يَتَعَاوَنْ |
لن تتعاون المؤسستان قبل توقيع الاتفاق.
lan tataʿāwana l-muʾassasatāni qabla tawqīʿi l-ittifāq.
The two institutions will not cooperate before the agreement is signed. (Singular verb in VSO.)
المؤسستان لم تتعاونا في المرحلة السابقة.
al-muʾassasatāni lam tataʿāwanā fī l-marḥalati s-sābiqa.
The two institutions did not cooperate in the previous phase. (Subject-first dual agreement.)
Weak, hamzated, and geminate roots
Final-weak تَنَامَى — يَتَنَامَى — تَنَامِيًا “grow progressively” (root ن-م-و) loses ى in the singular jussive: لم يتنامَ. Hamzated تَسَاءَلَ — يَتَسَاءَلُ — تَسَاؤُلًا “wonder; ask one another” (root س-ء-ل) changes the hamza seat in its verbal noun. Geminate تَضَادَّ — يَتَضَادُّ — تَضَادًّا “be opposed/contrast” (root ض-د-د) contracts the final two radicals under shadda.
لم يتنام الوعي بالمشكلة بالسرعة المتوقعة.
lam yatanāma l-waʿyu bil-mushkilati bis-surʿati l-mutawaqqaʿa.
Awareness of the problem did not grow at the expected rate.
تساءلت الخبيرتان عن مصدر الأرقام المتضاربة.
tasāʾalati l-khabīratāni ʿan maṣdari l-ʾarqāmi l-mutaḍāriba.
The two female experts wondered about the source of the conflicting figures.
Common Mistakes
Assuming every Form VI verb means “each other”
❌ تجاهلت الإدارة التحذير يعني أن الطرفين تجاهل أحدهما الآخر.
Incorrect analysis—تجاهل is lexically transitive ‘ignore’ here, not a reciprocal event.
✅ تجاهلت الإدارة التحذير رغم وضوحه.
tajāhalati l-ʾidāratu t-taḥdhīra raghma wuḍūḥih.
The administration ignored the warning despite its clarity.
Copying one preposition across all reciprocal verbs
❌ تبادل الباحثون مع الملاحظات.
Incorrect—تبادل takes the exchanged item directly; مع can introduce a partner separately.
✅ تبادل الباحثون الملاحظات مع فريق التحرير.
tabādala l-bāḥithūna l-mulāḥaẓāti maʿa farīqi t-taḥrīr.
The researchers exchanged comments with the editorial team. (Singular verb in VSO.)
Losing feminine agreement
❌ الباحثتان تفاوضا مع الشركة.
Incorrect after a feminine dual subject—use feminine dual تفاوضتا.
✅ الباحثتان تفاوضتا مع الشركة حول الجدول الزمني.
al-bāḥithatāni tafāwaḍatā maʿa sh-sharikati ḥawla l-jadwali z-zamaniyy.
The two female researchers negotiated with the company about the timeline.
Giving a verb-first clause full dual agreement
❌ تفاوضا المندوبان مع الوزارة.
Incorrect in neutral formal VSO—use singular تفاوض before an overt dual subject.
✅ تفاوض المندوبان مع الوزارة طوال الصباح.
tafāwaḍa l-mandūbāni maʿa l-wizārati ṭawāla ṣ-ṣabāḥ.
The two delegates negotiated with the ministry throughout the morning.
Regularizing a final-weak jussive
❌ لم يتنامى الوعي بالمشكلة.
Incorrect in careful MSA—final-weak يتنامى loses ى after jussive لم.
✅ لم يتنام الوعي بالمشكلة خلال الحملة.
lam yatanāma l-waʿyu bil-mushkilati khilāla l-ḥamla.
Awareness of the problem did not grow during the campaign.
Key Takeaways
- Form VI follows تَفَاعَلَ — يَتَفَاعَلُ — تَفَاعُلًا.
- Reciprocal and gradual meanings are common tendencies, while many verbs are fully lexicalized.
- Reciprocal participants may appear together in a plural subject or separately with مع.
- Agreement still depends on word order, and nonhuman plurals still take feminine-singular agreement.
- Verify weak, hamzated, and geminate principal parts instead of forcing the sound-root template.
Now practice Arabic
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning Arabic →Related Topics
- Form V تفعّلA2 — Build Form V from t- plus the Form II shape and distinguish reflexive, result, developmental, and fully lexicalized meanings.
- Form VII انفعلB1 — Recognize Form VII's n-prefix, hamzat al-waṣl, intransitive result meanings, and firm restrictions on which roots can enter the pattern.
- The Arabic Verb SystemA1 — See how Arabic verb stems, agreement, mood, voice, and derived Forms work together in complete sentences.