Question mark - Spelling - Part III. Style 20 spelling

A manual for writers of research papers, theses, and dissertations, 7th edition - Kate L. Turabian 2007

Question mark
Spelling
Part III. Style 20 spelling

Put a question mark at the end of a complete sentence phrased as a question. If the question mark is the terminal punctuation, it should be followed by a single space.

Who would lead the nation in its hour of need?

Put a question mark after a clause phrased as a question and included as part of a sentence. Do not use quotation marks unless the question is a quotation and the rest of the sentence is not.

Would the union agree? was the critical question.

If the included question is at the end of the sentence, do not add a period after the question mark. You are not required to capitalize the first word of the included question, but an initial capital helps readers identify the question, especially if it includes internal punctuation. If the sentence becomes awkward, you may instead rephrase the question as a declarative statement followed by a period.

Several legislators raised the question, Can the fund be used in an emergency, or must it remain dedicated to its original purpose?

Several legislators raised the question of using the fund in an emergency, which was not its original purpose.

A question mark may also indicate doubt or uncertainty, as in a date.

The painter Niccolò dell'Abbate (1512?—71) assisted in the decorations at Fontainebleau.