When to use a question mark

The question mark (?) has two main purposes - to signal a query for information or to express doubt around facts.

Question types -

* direct question - eg. Will you be visiting the museum on your trip?
* tag question - eg. We were leaving at 7am, weren't we?
* rhetorical question - eg. Aren't you all being nice and quiet?
* unspoken question - eg. When will it stop? she wondered to herself.

Doubt - a question mark may be employed where details are not certain.

eg. The victim stated he was walking through the park at 3pm (?) when the attack occurred.

When NOT to use a question mark:

* indirect questions - eg. Before leaving for a camping trip, ask yourself what equipment is essential.
* after single interrogative words in a sentence - eg. She wanted to know when she could start work on the project.
* standard requests - eg. Can you complete this task and return it to me by Friday.

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