Understanding the type of knots that are allowed to be opened on Shabbos.
How to Remove Gum When It Is Stuck in One's Hair, and How to Remove a Band-Aid;
What Do We Mean by Leaning on a Tree? Items on a Tree Going into Shabbos Remain Muktzeh;
Various Examples of Where We Have the Problem of דבר דבר (Dabair Davar) and ממצוא חפציך (Mimtzo Cheftzecha);