etymology
editPokorny links it to Czech skutek, kutit ("deed, do") and gives it the meaning of "things to do, to work"
the link with Russian sovať (posunout, posouvat, posun, posuv in Czech) seems to me wrong as my etymological dictionary links it with a S^P root (sypat, spát, "make fall, fall asleep") and not a S^K (as in *skew) one.