Possible Duplicate:
“How to […]?” and “Where to […]?” Questions that are not questions. Is this defensible?
Does it make sense, grammatically, to end the phrase "How to [action]" with a question mark, or is it more correct for the question mark to be omitted?
I've always considered this a sentence fragment at best, but maybe I'm mistaken. Is it a complete sentence? I tried and failed to identify a subject in any of the examples below, and without a subject I think they aren't complete sentences. If it isn't a complete sentence, is there such a thing as an implied subject that makes it grammatically valid to use the phrase as an interrogative sentence?
I'm asking because I see this all the time in question titles on SE sites.
Examples:
How to describe narrated action?
How to appropriately suggest title changes?