‘-ak’ is in fact the 2sgM form, the 2sgF form is ‘-ek’ (Cowell 1964:539). In addition, this form surfaces as ‘-k’ when suffixed to verb with a final vowel (Cowell 1964:540).
This form is only used with third person subjects, while the alternate form 'ro-' is used only with first person subjects (Gregores and Suárez 1967:131-2).
