Fly by night
The phrase "fly by night" typically refers to a person or situation that seems unreliable, untrustworthy, or lacking in stability. It often implies a sense of fleeting or temporary existence, suggesting that the person or thing may vanish or disappear quickly without leaving a lasting impact. "Fly by night" can also describe behaviors or activities that are secretive, dishonest, or conducted under the cover of darkness.
English is confusing! Why do people say "Pardon my French" when they are speaking English? Because of idioms!
An idiom is a phrase or expression that usually presents a figurative, non-literal meaning attached to the phrase. Does that sound fun? It can be!
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