Learn Arabic (Modern Standard): اتضحت رؤيتنا بعد الاجتماع. - Our vision became clear after the meeting.

The root is و ض ح (w-D-H), meaning clarity. Since this is a Form VIII verb, we add an Alif at the beginning and a Taa' after the first root letter. Normally, this would give us اوتضحت (iwtaDahat). However, as you are learning in this lesson, when a Form VIII root starts with a Waaw (و), the Waaw merges into the inserted Taa' to make pronunciation easier. This creates a doubled Taa' (تّ), making the word اتّضحت (ittaDahat).

Why does the verb اتضحت end with a second Taa' (ت)?

The final ت is the feminine past-tense suffix (ـتْ), making the verb mean she or it became clear. The verb is feminine because the subject doing the action is رؤيتنا (our vision). The base noun for vision is رؤية (ru'ya), which ends in a Taa' MarbuuTa (ة) and is grammatically feminine.

Why is the Hamza in رؤيتنا written over a Waaw (ؤ)?

Middle Hamza spelling rules rely on the vowels around it. In رؤيتنا (ru'yatunaa), the Hamza itself has no vowel (it has a sukoon), but the letter right before it (Raa') has a u-vowel (Damma). Because the u-vowel is stronger than a sukoon, the Hamza takes the seat that matches the u-sound, which is the Waaw.

Is الاجتماع also related to Form VIII?