Stop pretending you know what you're talking about. You don't have a clue. The commas go inside the quotation marks even if they are not part of the original material (as is usually the case).
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Put commas and periods within closing quotation marks, except when a parenthetical reference follows the quotation.
"He likes to talk about football," she said, "especially when the Super Bowl is coming up."
In his poem "Mending Wall," Robert Frost questions the building of barriers and walls:[...]
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Of course I can write "a f****ng stupid." "Stupid" is also a noun, not only an adjective. You should know this.
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Also, inside double quotation marks you use _single_ quotation marks.
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And finally, it is "it's," not "its."
Congratulations.