The idiom "tell it to the marines" means that you don't believe what someone is saying or that you think they are lying. It's a way of expressing skepticism or disbelief.
The origin of this idiom is unclear, but it is believed to have originated in the British Navy. Sailors would often tell tall tales, and when someone didn't believe them, they would say, "tell it to the marines." The marines were seen as more gullible and less experienced than the sailors, so they were more likely to believe the stories.
You can use this idiom in a variety of situations. For example, if someone tells you a story that seems too good to be true, you can respond by saying, "tell it to the marines." It's a way of expressing your skepticism without being rude.
In summary, "tell it to the marines" is an idiom that means you don't believe what someone is saying. It's a way of expressing skepticism or disbelief in a polite way.
• "I once met a mermaid on the beach." - "Tell it to the marines."
• "I'm sure I can finish this project by tomorrow." - "Tell it to the marines."
• "I saw a unicorn yesterday!" - "Tell it to the marines."
• "I'm going to be a millionaire by next week." - "Tell it to the marines."
• "I have a plan to solve world hunger by next year." - "Tell it to the marines."
• "I have a secret formula that can cure cancer." - "Tell it to the marines."