It's wrong to take something that belongs to someone else.
Stacey always brings lunch to work, but today she forgot her lunch.
Stacey wants to wants to get something to eat.
Stacey decides to go to the cafeteria to see if she can get something for lunch.
Stacey looks in the fridge in the break room and takes a coworker's sandwich to eat.
Stacey enjoys her lunch and thinks that she will eat in the cafeteria more often.
Another coworker sees Stacey take the sandwich and tells her she shouldn't take someone else's lunch.