Have you ever heard the Japanese expression "寝耳に水" (ne mimi ni mizu)? This phrase, which translates to "water in a sleeping ear," is commonly used to describe a situation that comes as a complete surprise. It is similar to the English idioms "a bolt from the blue" or "out of the blue." The origin of this expression is quite interesting, with two main theories: one suggests it comes from the shock of hearing the sound of a flood while sleeping, and the other posits it originates from the sudden sensation of water entering one's ear while asleep. Both scenarios convey the idea of being startled by an unexpected event. This phrase can be used for both good and bad surprises. For instance, you might say, "I won the lottery? That's a bolt from the blue!" or "School is canceled tomorrow? That came out of the blue." Another similar Japanese expression is "青天の霹靂" (seiten no hekireki), which means "a bolt from the blue sky," also indicating a sudden and unforeseen event. Using "寝耳に水" in daily conversations can make them more engaging, especially when discussing surprising news or events.