1. Every Friday, that man comes in to the police station and says he thinks he has been robbed, but when we get to his house, there is never anything missing. I think he’s just crying wolf. You can’t believe him anymore.
2. Terry regularly lied to his mother, saying that his older brother hit him on the head. Terry did it so frequently that she stopped believing him and told him that one day he would be sorry that he had cried wolf so often.

The expression originates from one of Aesop’s fables in which a young shepherd boy falsely alerts people that a wolf is attacking the sheep. At first, people respond to the boy’s cries, but he cries “wolf” so many times just for fun that eventually they stop. When the wolf really does come and the boy cries “wolf,” no one comes to his aid.