Common mistakes
The root ends in و or ي, and the endings themselves change. Three patterns cover it: دَعَا يَدْعُو, رَمَى يَرْمِي and نَسِيَ يَنْسَى.
نَادَوَ → نَادَى Past: heنَادَوَتْ → نَادَتْ Past: sheنَادَوْتَ → نَادَيْتَ Past: you (m.)نَادَوْتُ → نَادَيْتُ Past: I