Other issues to watch out for when food, wax, etc. is attached to the part where there is no letters, numbers, etc.
Getting a Better Picture as to Why We Have Separate Melachas. Pouring Items from Hand to Hand;
important concepts pertaining to כלים (utensils);
Measuring for a mitzvah - "מדידה של מצוה". Preferably should be done on "ערב שבת".