Understanding the concept of separating "pesoles" (bad) from "pesoles"(bad).
Ex. Separating recycling from the rest.
what do we call "קיימא" (permanence) when dealing with stickers on clothing and other items;
(Temporary Ohel) What to do with an umbrella that somebody forgot to close;
(Melting ice.) placing water or juice into the freezer; making ice cubes;