The poor abused question mark (?) finds itself in the most mysterious of places.
Consider this sentence: Guess how many jellybeans I had for breakfast. So many people plop a question mark on the end. They’re wrong. That’s an imperative form (a command or directive), not an interrogative (question). You are telling your audience to do something; therefore, it takes a period.
It could be put in interrogative form, certainly: Can you guess how many jellybeans I had for breakfast? The answer, of course, is: Given that I couldn’t care less, no.
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