deriv LSK ETT STT aSTA ALPH OLDHOMEPAGE NEWHOMEPAGE
The root /as "there is" (aka /asti) is an /adAdi, so it gets no /zap.
In the /laT /loT, keeps its a अ it only before /pit endings, by znasorallopaH.
/as + /laT /tip → **asti अस्ति
/as + /jhi → **santi सन्ति
/as + /thas → **sthas स्थस्
/as + /mip → **asmi अस्मि
/as + /vas → **svas स्वस्
/as + /mas → **smas स्मस्