vbal pref
― of imperf before vbal subj
―― before nominal subj (S) ⲛⲉⲣⲉ- (AB) ⲛⲁⲣⲉ-
― plupf
― past aorist
― neg plupf with ⲙⲡⲉ-
ⲛⲉ- in nominal clause indicates past