Using utensils, items that open and close by folding. (E.g., folding tables, strollers, playpens, folding chairs, etc.)
הכנה לחול (Preparations for a Weekday): Doing an Action and Using Only Part of the Outcome. Doing an Act on Shabbos Simply to Save...
Is One Allowed to Learn for a Test During the Week?;
What are some of the halachas of "kevashim/shlokos" (various foods). Part 2.