דבר דבר (Dabair Davar): Making Calculations on Events Which Already Took Place Before Shabbos;
Putting the Little Plastic or Rubber Cups on the Bottom of Chairs or Tables and Blowing Bubbles on Shabbos;
Understanding the Concept of Something That Was Attached to the Ground or a Tree Going into Shabbos and Then Became Detached on Shabbos (Muktzeh);