irrt[4], trat[4], ritt[4], raut[4], trau[4], urat[4], taut[4],
air[3], rai[3], rar[3], irr[3], tai[3], art[3], rat[3], tat[3], rau[3], tau[3], tut[3],
ai[2], ar[2], ti[2], au[2], ui[2], ur[2], tu[2],
