Yes, but it makes the statement rather indecisive -
* The quick brown fox jumped over the lazy dog? (maybe the dog wasn't lazy, but simply resting after a hard day chasing cats)
* I have a sore thumb? (at least I think it's my thumb. It could be a finger... or perhaps a toe. Maybe it's someone else's thumb) * People who can't read are illiterate? (maybe they're just stupid)
* I have gas? (putting a '?' on that statement makes it go from "hold your nose" to "change your drawers" (?))
* Putting a question mark at the end of a statement makes it a question?(or even an elephant)