Use this diagnostic summary to distinguish the key outcomes:
CategoryFormMeaning
active perfectرَمَىhe threw
passive perfectرُمِيَit was thrown
active imperfectيَرْمِيhe throws
passive imperfectيُرْمَىit is thrown
lanلَنْ يَرْمِيَhe will not throw
lamلَمْ يَرْمِhe did not throw
imperativeاِرْمِthrow!
prohibitionلَا تَرْمِdo not throw
active participleرَامٍthrower
passive participleمَرْمِيٌّthrown
For a new weak-final form, ask four questions: What is its root? Which person and voice is it? Which particle or morphological pattern governs it? What happens to the weak consonant?