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MOTTOES

A motto or slogan of only a few words is capped as in the original and put within quotation marks:
            The flag's message read "Don't Tread on Me."
             ... their motto, "Be Prepared."
             ... the researcher's motto, "Accuracy! Accuracy!! Accuracy!!!"

A longer motto or slogan may use initial cap only:
            the Annapurna motto, "A woman's place is on top."
             the slogan "All for one, one for all."

A foreign motto or slogan is italicized within quotation marks; the translation is in roman, capped as appropriate, and put within quotation marks:
            The Marine motto, "Semper Fidelis—Always Faithful."
             "Ducit Amor Patriae, Love of Country Leads."
             They shouted, "Harambee!" meaning "Let us pull together!"
             "Long live the great, glorious, and absolutely correct
                        Communist Party" reads a red billboard on Chang'an Avenue.