The active second-person masculine forms address one man, two men or a group of men. All three begin with تَ.
Word / formMeaning / explanation
Singular: تَفْعَلُyou (one man) do / will do.
Dual: تَفْعَلَانِyou two men do / will do.
Plural: تَفْعَلُونَyou men do / will do.
تَفْعَلُ is also the surface form for third-person feminine singular. The explicit pronoun أَنْتَ or context identifies the second-person meaning.