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Headlines and Titles of Works
Q. Do you capitalize the preposition for in headline-capitalization style in this case: “XYZ: what is it good for?” Lowercase or uppercase? Thanks a lot!
A. The last word is capitalized in a Chicago-style headline-capped title, regardless of syntax: “XYZ: What Is It Good For?” Please see CMOS 8.159 (point 1) for this rule.