Memory Idioms 2Versión en línea Players will try to match the idiom with it's meaning. por Lunarn Smith Once in a blue moon Work until late at night Wait and be patient Best thing since sliced bread Burn the midnight oil It’s not hard. It’s not rocket science Ants in one’s pants Cost an arm and a leg Let the cat out of the bag Hold your horses Can’t stay calm (relax) because you’re nervous Very expensive Tell a secret Good idea or invention Don’t start problems or cause trouble Let sleeping dogs lie Happens very rarely; uncommon