When to use A qué or Qué in a question?

When to use A qué or Qué in a question?
 

I have a problem, sometimes on my writing I'm using ¿Qué to start a question and sometimes I'm using ¿A qué - could someone clear up why and when I should use ¿A qué to begin questions in Spanish?

Saludos. ^_^

You always use "¿Qué...?" whenever "qué" is the subject, and you usually use it when it is the direct object of the verb. Otherwise, you must use "¿[preposition] qué...?". The correct preposition depends on the role that "qué" has in relation to the verb: it may be the indirect object, or it may be the object of some preposition. For example:

¿De qué hablas? = What are you talking about?

It might help you to remember that in Spanish you can't end a phrase in a preposition.

This rule doesn't apply to English, but you can reword English to make it easier to translate the phrase into Spanish.

What are you talking about?
becomes
About what are you talking?

What destination are you going to?
becomes
To what destination are you going?

Whom are you talking to?
becomes
To whom are you talking?

Thank you very much Rusty, that was an excellent explanation.

Thanks. Saludos. :)