Understanding the concept of separating "pesoles" (bad) from "pesoles"(bad).
Ex. Separating recycling from the rest.
(Melting ice.) breaking the ice cubes to remove them from the ice tray; pouring hot liquids onto ice cubes (from a kli shieni);
(Squeezing materials.) the correct procedure in reference to wiping up spills on a counter, table or floor with a towel or rag;
The halachas of opening food packages with letters, numbers, pictures.