NEVER, EVER send in your only copy of your manuscript. If it's printed, or if it's a doc. Almost all (if not all) publishing houses send back your manuscript. They usually recycle the sample chapters (or complete manuscript) if they reject you.
If they like your manuscript and accept it I don't know what they do with the copy you gave them because I have not been able to get anyone to even read my complete manuscript yet. Hopefully you have better luck :)
Anyway, never send in your only printed copy of your manuscript. Always keep an extra lying around.
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