Is one allowed to drink the juices which oozed out during eating; grapefruit issues.
fixing a Hat, Dust on a Hat, a Dent in an Aluminum Foil Pan, Plastic Fruit Cup, and Shaking Down a Thermometer;
(Melting ice.) putting ice into drinks; breaking off pieces of ice;
(Squeezing materials.) how to work with various types of brushes on Shabbos. (E.g., toothbrush, baby bottle brush, etc.);