There is more than one answer to this question because different areas seem to have adapted it to suit them. Answers are
1) Dead as a Dodo.
2) Dead as a Door nail.
3) Dead as Door knocker.
A quote which is incorporated within a sentence where it makes sense with the rest of the sentence.
That actually isn't the full quote. Here it is: "A life of leisure and a life of laziness are two things. There will be sleeping enough in the grave." - Benjamin Franklin It means that now is not a time to be lazy. You can rest when you're dead.
Hamlet
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"If the horse is dead, get off it".
Mannix - 1967 To Quote a Dead Man 6-22 was released on: USA: 25 February 1973
If you are in the 'chapel of rest' then you will probably be dead. It is commonly found in the undertaker's mortuary - where the dead are kept before the funeral.
"Ladies and Gentlemen...I am not dead"
It's a quote from the movie "Hackers".
Either "So shall it be," or "So shall it be done."
Only when you're dead.
"Three can keep a secret, if two of them are dead."