Is the period inside or outside quotation marks?

Mark the full stop position as appropriate.

When the quoted sentence is a complete sentence and needs to be used independently, then the period at the end of the quoted sentence should be enclosed in quotation marks. For example, Confucius said, "Don't do to others what you don't want others to do to you."

If quotation marks are part of the whole sentence, then periods should be placed outside quotation marks. For example, Engels once profoundly pointed out that "the movement itself is a contradiction". At this time, the quotation is not used independently, but only part of the whole sentence. The period marks the end of the whole sentence, not the result of quotation marks, so the period should be placed outside quotation marks.