In the simple singular and first-person positions, the heavy nūn is generally preceded by a fatḥa. The normal indicative final ḍamma does not remain before the emphatic ending.
Word / formMeaning / explanation
يَفْعَلُ ← لَيَفْعَلَنَّhe will certainly do.
تَفْعَلُ ← لَتَفْعَلَنَّyou (masc.) will certainly do, or she will certainly do.
أَفْعَلُ ← لَأَفْعَلَنَّI will certainly do.
نَفْعَلُ ← لَنَفْعَلَنَّwe will certainly do.
Person remains crucial even when several forms look alike at their ends.