The textbook lists six forms, distinguishing masculine/feminine and singular/dual/plural.
Word / formMeaning / explanation
فَاعِلٌone male doer.
فَاعِلَانِtwo male doers.
فَاعِلُونَmale doers (plural).
فَاعِلَةٌone female doer.
فَاعِلَتَانِtwo female doers.
فَاعِلَاتٌfemale doers (plural).
The displayed examples are nominative forms. Noun endings may vary with grammatical case.