Compare representative active forms across person and number:
PronounHeavy nūnLight nūn
heلَيَرْمِيَنَّلَيَرْمِيَنْ
they two (m.)لَيَرْمِيَانِّ—
they (m.)لَيَرْمُنَّلَيَرْمُنْ
sheلَتَرْمِيَنَّلَتَرْمِيَنْ
Iلَأَرْمِيَنَّلَأَرْمِيَنْ
The heavy and light emphatic constructions are not simple addition of a nūn to the unchanged indicative. Their interaction with the weak stem and personal endings needs to be read form by form. This selection illustrates the textbook's full tables.