interrogative word order
Interrogative word order is used to pose questions, with or without an expected answer. Most of the time, it is formed by switching the order of the subject and the auxiliary (or "helping") verb in a declarative sentence, as in the following:

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1. Are you going to the party?
2. Is he supposed to do that?
3. How much do I owe you?
4. Where is the parking lot?

However, when the information being requested would be the subject of the answer, the word order is not inverted, and the interrogative pronoun takes the place of the subject, as in the following:

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1. Who helped you with your homework?
2. What happened here?

When spoken, an intonation change is often used so as to emphasize this switch, or can entirely reflect the interrogative mood in some cases (e.g. "John ran?"). The interrogative phrase can further be formed in this manner by moving the predicate of a declarative sentence in front of the helping verb and changing it to a demonstrative, relative pronoun, quantifier, etc. The interrogatives phrase is denoted by ending the sentence with a question mark .

Rhetorical questions can be formed by moving the helping verb-subject pair to the end of the question, e.g. "You wouldn't really do that, would you?"