Fictional rules invented by girls to confused guys, during a relationship. Generally, these rules contradict eachother, and it is impossible to follow them correctly.
There is the common "statement" form, encountered when an action is illegal:
"John! You moved my lettuce to shelf four of the refridgerator! that is so against the rules!"
Also common is the "impossible question" form, where no correct answer is possible:
"Tim. Does this dress make me look fatter than normal?"
"Do you know what day it is today?"
Rare, but still worth mentioning, is the "invented" form:
"This form was invented to fill up some space on the page"