Definition:
If any triliteral rooted verb's second and third of the three root letters is the same letter then that is defined as the doubled verb. When the third letter contains a vowel, then second and third letters are combined and written with a shadda over the second letter signifaying the doubling. Below given examples demonstrate this rule.

The dual form is not used in daily life. It is usually an academic interest. Therefore, we will skip the dual form from our tables.

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FORM-1, weak verb = wadda = to love, root = و-د-د masc=m, fem=f English Pronouns Arabic Pronouns   Perfect   Imperfect I anaa (أَنَا) wadadtu (وَدَدْتُ) awaddu (أَوَدُّ) Thou (m) anta (أَنْتَ) wadadta (وَدَدْتَ) tawaddu (تَوَدُّ) Thou (f) anti (أَنْتِ) wadadti (وَدَدْتِ) tawaddiyna (تَوَدِّينَ) He huwa (هُوَ) wadda (وَدَّ) yawaddu (يَوَدُّ) She hiya (هِيَ) waddat (وَدَّتْ) tawaddu (تَوَدُّ) We nahnu (نَحْنُ) wadadnaa (وَدَدْنَا) nawaddu (نَوَدُّ) You (m) antum (أَنْتُمْ) wadadtum (وَدَدْتُمْ) tawadduuna (تَوَدُّونَ) You (f) antunna (أَنْتُنَّ) wadadtunna (وَدَدْتُنَّ) tawdadna (تَوْدَدْنَ) They (m) hum (هُمْ) wadduu (وَدُّوا) yawadduuna (يَوَدُّونَ) They (f) hunna (هُنَّ) wadadna (وَدَدْنَ) yawdadna (يَوْدَدْنَ)

FORM-1, weak verb=shakka=to doubt   Perfect   Imperfect shakaktu (شَكَكْتُ) ashukku (أَشُكُّ) shakakta (شَكَكْتَ) tashukku (تَشُكُّ) shakakti (شَكَكْتِ) tashukkiyna (تَشُكِّينَ) shakka (شَكَّ) yashukku (يَشُكُّ) shakkat (شَكَّتْ) tashukku (تَشُكُّ) shakaknaa (شَكَكْنَا) nashukku (نَشُكُّ) shakaktum (شَكَكْتُمْ) tashukkuuna (تَشُكُّونَ) shakaktunna (شَكَكْتُنَّ) tashkukna (تَشْكُكْنَ) shakkuu (شَكُّوا) yashukkuuna (يَشُكُّونَ) shakakna (شَكَكْنَ) yashkukna (يَشْكُكْنَ)

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