Stone monument that includes the same passage carved in hieroglyphics, demotic script, and greek and that was used to decipher the meanings of many hieroglyphics is called .

The Rosetta Stone

Explanation:

You might have heard of this stone before. It is a popular language learning app but it also is an ancient stone that helped people to decipher ancient Egyptian hieroglyphics. It has a message in hieroglyphics and demotic script with a Greek translation on the bottom, so people were able to figure out what many of the hieroglyphs meant.

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