"Morson's" Rule 2 says to use a period to end a request, a gentle command, or a suggestion phrased in the form of a question. "Bad Grammar / Good Punctuation" Period.20 also says to use a period. Wells adds that the only response to a polite request cannot be "yes" or "no." To help identify polite requests, look for questions beginning with "will," "would," or "may."